Storage and retrieval system

ABSTRACT

A product order fulfillment system includes multiple decks arrayed at different levels and defining multilevel decks, at least one autonomous transport vehicle on each of the decks, and configured for holding and transporting a pickface on each deck, at least one lift, traversing and connecting more than one level of the decks, and arranged for lifting and lowering the pickface from the decks, and at least one pickface transfer station on each deck interfacing between the transport vehicle and the at least one lift to effect transfer of the pickface between the transport vehicle and the at least one lift, the at least one lift defines a fulfillment stream of mixed case pickfaces outbound from the multilevel decks to a load fill, at least one stream of the fulfillment stream has an ordered sequence of streaming pickfaces wherein the ordered sequence of streaming pickfaces is based on another fulfilment stream.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. non-provisional patentapplication Ser. No. 16/950,383, filed on Nov. 17, 2020, (now U.S. Pat.No. 11,562,321),which is a continuation of U.S. non-provisonal patentapplication Ser. No. 16/718,918, filed on Dec. 18, 2019, (now U.S. Pat.No. 10,839,347), which is a continuation of U.S. non-provisional patentapplication Ser. No. 16/162,247, filed on Oct. 16, 2018, (now U.S. Pat.No. 10,521,767), which is a continuation of U.S. non-provisional patentapplication Ser. No. 14/997,925, filed on Jan. 18, 2016, (now U.S. Pat.No. 10,102,496), which claims priority from and the benefit of U.S.Provisional Patent Application No. 62/104,531 filed on Jan. 16, 2015,the disclosures of which are incorporated by reference herein in theirentireties.

This application is also related to U.S. patent application Ser. No.15/890,088 filed on Feb. 6, 2018, which is a continuation of U.S. patentapplication Ser. No. 14/966,978, filed on Dec. 11, 2015, (now U.S. Pat.No. 9,884,719 issued on Feb. 6, 2018); U.S. patent application Ser. No.14/997,892, filed on Jan. 18, 2016; U.S. patent application Ser. No.14/997,902, filed on Jan. 18, 2016; U.S. patent application Ser. No.15/848,809, filed on Dec. 20, 2017, which is a continuation of U.S.patent application Ser. No. 14/997,920, filed on Jan. 18, 2016 (now U.S.Pat. No. 9,856,083 issued on Jan. 2, 2018); and U.S. Provisional PatentApplication No. 62/107,135, filed on Jan. 23, 2015, the disclosures ofwhich are incorporated herein by reference in their entireties.

BACKGROUND 1. Field

The exemplary embodiments generally relate to material handling systemsand, more particularly, to transport and storage of items within thematerial handling system.

2. Brief Description of Related Developments

Multilevel storage and retrieval systems may be used in warehouses forthe storage and retrieval of goods. Generally the transportation ofgoods into and out of the storage structure is done with lifts fortransfer to a vehicle on a storage level, vehicles travelling up rampsto a predetermined storage level, or with vehicles that include liftstraveling along guide ways. Goods stored within the storage andretrieval system are generally stored in storage spaces on each storagelevel such that a transport vehicle disposed on that level has access toone level of storage spaces. Generally, the lifts that transfer items toand from the storage spaces carry the vehicles between different storagelevels, are incorporated into the vehicles (such as with a gantry crane)or have a paternoster configuration where the lift payload shelvescontinually circulate around a frame at a predetermined rate.

Generally sequencing of items picked from storage is performed by thevehicles picking the items or by a dedicated sorter that sorts the itemsduring an outbound flow after being transported by the gantry crane orpaternoster lift. The sorting of outbound items in this manner mayresult in the lifts performing multiple lift strokes to pick the itemsneeded for a load-out or additional sorting steps thereby decreasingthroughput of the storage and retrieval system.

It would be advantageous to increase a rate of item transfer to and fromthe different storage levels within a storage and retrieval system whereitems of a load-out are sorted at a lift interface and picked with acommon lift stroke and where an order of sorted items at the liftinterface is matched to a load stream of a common load, lift interfaceand/or lift.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the disclosed embodiment areexplained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a schematic illustration of an automated storage and retrievalsystem in accordance with aspects of the disclosed embodiment;

FIG. 1A is a schematic illustration of a portion of the storage andretrieval system in accordance with aspects of the disclosed embodiment;

FIG. 1B is a schematic illustration of a portion of the storage andretrieval system in accordance with aspects of the disclosed embodiment;

FIG. 1C is a schematic illustration of a portion of the automatedstorage and retrieval system in accordance with aspects of the disclosedembodiment;

FIG. 2 is a schematic illustration of a mixed pallet load formed by theautomated storage and retrieval system in accordance with aspects of thedisclosed embodiment;

FIGS. 3A and 3B are schematic illustrations of portions of the storageand retrieval system in accordance with aspects of the disclosedembodiment;

FIGS. 4A and 4B are schematic illustrations of portions of the storageand retrieval system in accordance with aspects of the disclosedembodiment;

FIGS. 5A, 5B, 5C, 5D and 5E are schematic illustrations of portions ofthe storage and retrieval system in accordance with aspects of thedisclosed embodiment;

FIG. 6 is a schematic illustration of a portion of the storage andretrieval system in accordance with aspects of the disclosed embodiment;

FIG. 6A is a flow diagram in accordance with aspects of the disclosedembodiment;

FIGS. 7, 7A-7E are schematic illustrations of a portion of the storageand retrieval system in accordance with aspects of the disclosedembodiment;

FIGS. 8-13 are flow diagrams in accordance with aspects of the disclosedembodiment;

FIG. 14 is a schematic illustration of an operator station of thestorage and retrieval system in accordance with aspects of the disclosedembodiment; and

FIG. 15 is an exemplary flow diagram in accordance with aspects of thedisclosed embodiment.

DETAILED DESCRIPTION

FIG. 1 is a schematic illustration of an automated storage and retrievalsystem 100 in accordance with aspects of the disclosed embodiment.Although the aspects of the disclosed embodiment will be described withreference to the drawings, it should be understood that the aspects ofthe disclosed embodiment can be embodied in many forms. In addition, anysuitable size, shape or type of elements or materials could be used.

In accordance with aspects of the disclosed embodiment the automatedstorage and retrieval system 100 may operate in a retail distributioncenter or warehouse to, for example, fulfill orders received from retailstores for case units such as those described in U.S. patent applicationSer. No. 13/326,674 filed on Dec. 15, 2011, the disclosure of which isincorporated by reference herein in its entirety. For example, the caseunits are cases or units of goods not stored in trays, on totes or onpallets (e.g. uncontained). In other examples, the case units are casesor units of goods that are contained in any suitable manner such as intrays, on totes or on pallets. In still other examples, the case unitsare a combination of uncontained and contained items. It is noted thatthe case units, for example, include cased units of goods (e.g. case ofsoup cans, boxes of cereal, etc.) or individual goods that are adaptedto be taken off of or placed on a pallet. In accordance with the aspectsof the disclosed embodiment, shipping cases for case units (e.g.cartons, barrels, boxes, crates, jugs, or any other suitable device forholding case units) may have variable sizes and may be used to hold caseunits in shipping and may be configured so they are capable of beingpalletized for shipping. It is noted that when, for example, bundles orpallets of case units arrive at the storage and retrieval system thecontent of each pallet may be uniform (e.g. each pallet holds apredetermined number of the same item—one pallet holds soup and anotherpallet holds cereal) and as pallets leave the storage and retrievalsystem in a load-out the pallets may contain any suitable number andcombination of different case units (e.g. a mixed pallet where eachmixed pallet holds different types of case units—a pallet holds acombination of soup and cereal) that are provided to, for example thepalletizer in a sorted arrangement for forming the mixed pallet. In theembodiments the storage and retrieval system described herein may beapplied to any environment in which case units are stored and retrieved.

Also referring to FIG. 2 , as noted above, when, for example, incomingbundles or pallets (e.g. from manufacturers or suppliers of case unitsarrive at the storage and retrieval system in a load-in forreplenishment of the automated storage and retrieval system 100, thecontent of each pallet may be uniform (e.g. each pallet holds apredetermined number of the same item—one pallet holds soup and anotherpallet holds cereal). As may be realized, the cases of such pallet loadmay be substantially similar or in other words, homogenous cases (e.g.similar dimensions), and may have the same SKU (otherwise, as notedbefore the pallets may be “rainbow” pallets having layers formed ofhomogeneous cases). As pallets PAL leave the storage and retrievalsystem 100 in a load-out, with cases filling replenishment orders, thepallets PAL may contain any suitable number and combination of differentcase units CU (e.g. each pallet may hold different types of case units—apallet holds a combination of canned soup, cereal, beverage packs,cosmetics and household cleaners). The cases combined onto a singlepallet may have different dimensions and/or different SKU's. In theexemplary embodiment, referring also to FIG. 1B, the storage andretrieval system 100 is configured to generally include an in-feedsection (including one or more input stations 160IN), a storage andsortation section 100SS (including, in one aspect, multilevel casestorage 170, horizontal case transport 171, case buffering and verticalcase transport 173) and an output section 100US (including one or moreoutput stations 160UT) as will be described in greater detail below. Inother aspects one or more of the case buffering 172 and vertical casetransport 173 are included in the output section 100US while in stillother aspects the case buffering 172 and vertical case transport 173 arecommon to both the storage and sortation section 100SS and the outputsection 100US. As may be realized, in one aspect of the disclosedembodiment, the system 100 operating for example as a retaildistribution center may serve to receive uniform pallet loads of cases,breakdown the pallet goods or disassociate the cases from the uniformpallet loads into independent case units handled individually by thesystem, retrieve and sort the different cases sought by each order intocorresponding groups, and transport and assemble the correspondinggroups of cases into what may be referred to as mixed case pallet loadsMPL. As may also be realized, as illustrated in FIG. 14 , in one aspectof the disclosed embodiment the system 100 operating for example as aretail distribution center may serve to receive uniform pallet loads ofcases, breakdown the pallet goods or disassociate the cases from theuniform pallet loads into independent case units handled individually bythe system, retrieve and sort the different cases sought by each orderinto corresponding groups, and transport and sequence the correspondinggroups of cases (in the manner described herein) at an operator station160EP where items are picked from the different case units CU, and/orthe different case units CU themselves, are placed in one or morebag(s), tote(s) or other suitable container(s) TOT by an operator 1500,or any suitable automation, in a predetermined order sequence of pickeditems according to, for example, an order, fulfilling one or morecustomer orders, in which the case units CU are sequenced at theoperator station 160EPin accordance with the predetermined ordersequence, noting that the sequencing of the case units CU as describedherein effects the sequencing of the case units CU at the operatorstation 160EP.

The in-feed section may generally be capable of resolving the uniformpallet loads to individual cases, and transporting the cases viasuitable transport, for input to the storage and sortation section. Thestorage and sortation section in turn may receive individual cases,store them in a storage area and retrieve desired cases individually inaccordance with commands generated in accordance to orders entered intoa warehouse management system for sequenced 174 transport to the outputsection 100US. The sorting and grouping of cases according to order(e.g. an order or load out sequence) may be performed in whole or inpart by either the storage and sortation section 100SS or the outputsection 100US, or both, the boundary between being one of conveniencefor the description and the sorting and grouping being capable of beingperformed any number of ways. For example, as noted above, while thecase buffering 172 and vertical case transport 173 are shown in FIG. 1Bas being included in the storage and sortation section 100SS, in otheraspects one or more of the case buffering 172 and vertical casetransport 173 are included in the output section 100US and/or are commonto both the storage and sortation section 100SS and the output section100US. The intended result is that the output section assembles theappropriate group of ordered cases, that may be different in SKU,dimensions, etc. into, in one aspect, mixed case pallet loads in themanner described in, for example, U.S. patent application Ser. No.13/654,293 filed on Oct. 17, 2012 (now U.S. Pat. No. 8,965,559), thedisclosure of which is incorporated herein by reference in its entirety,while in other aspects the output section assembles the appropriategroup of ordered case units, that may be different in SKU, dimensions,etc. into bags, totes or other suitable containers according to thepredetermined order sequence of picked items at the operator station160E (such as to e.g., fill a customer order).

In one aspect of the exemplary embodiment, the output section 100USgenerates the pallet load in what may be referred to as a structuredarchitecture of mixed case stacks. The structured architecture of thepallet load may be characterized as having several flat case layersL121-L125, L12T, at least one of which is formed of non-intersecting,free-standing and stable stacks of multiple mixed cases. The mixed casestacks of the given layer have substantially the same height, to form asmay be realized substantially flat top and bottom surfaces of the givenlayer, and may be sufficient in number to cover the pallet area, or adesired portion of the pallet area. Overlaying layer(s) may beorientated so that corresponding cases of the layer(s) bridge betweenthe stacks of the supporting layer. Thus, stabilizing the stacks andcorrespondingly the interfacing layer(s) of the pallet load. In definingthe pallet load into a structured layer architecture, the coupled 3-Dpallet load solution is resolved into two parts that may be savedseparately, a vertical (1-D) part resolving the load into layers, and ahorizontal (2-D) part of efficiently distributing stacks of equal heightto fill out the pallet height of each layer. In other aspects the loadfill of mixed cases may be configured in any other suitable orderedsequence and may be loaded on or in any suitable transport device suchas, for example, a bag, tote, shopping carriage, a truck or othersuitable container fill without palletization. As will be describedbelow, the storage and retrieval system outputs case units to the outputsection so that the two parts of the 3-D pallet load solution areresolved, while in other aspects the storage and retrieval systemoutputs case units to the output section according to a sequence forfilling non-palletized item picking sequence orders at the operatorstation 160EP. The term load fill or container fill as used hereinrefers to case units that are delivered to either a pallet load fillsection/cell (such as for the creation of a mixed pallet load MPL) or anitemized load fill section/cell as described with respect to FIG. 14where both the pallet load fill section/cell and the itemized load fillsection/cell are referred to generally as load fill section/station orcell.

In accordance with aspects of the disclosed embodiment, referring againto FIG. 1 , the automated storage and retrieval system 100 includesinput stations 160IN (which include depalletizers 160PA, operatorstations 160EP and/or conveyors 160CA for transporting items to liftmodules for entry into storage) and output stations 160UT (which includepalletizers 160PB and/or conveyors 160CB for transporting case unitsfrom lift modules for removal from storage), input and output verticallift modules 150A, 150B (generally referred to as lift modules 150—it isnoted that while input and output lift modules are shown, a single liftmodule may be used to both input and remove case units from the storagestructure), a storage structure 130, and a number of autonomoustransport vehicles 110 (referred to herein as “bots”). As used herein atleast the lift modules 150, storage structure 130 and bots 110 may becollectively referred to herein as the storage and sortation sectionnoted above. It is also noted that the depalletizers 160PA may beconfigured to remove case units from pallets so that the input station160IN can transport the items to the lift modules 150 for input into thestorage structure 130. The palletizers 160PB may be configured to placeitems removed from the storage structure 130 on pallets PAL (FIG. 2 )for shipping.

Also referring to FIG. 3A, the storage structure 130 may includemultiple storage rack modules RM, configured in a three dimensionalarray RMA, that are accessible by storage or deck levels 130L. Eachstorage level 130L includes storage spaces 130S formed by the rackmodules RM where the rack modules include shelves that are disposedalong storage or picking aisles 130A which, e.g., extend linearlythrough the rack module array RMA and provide access to the storagespaces 130S and transfer deck(s) 130B over which the bots 110 travel ona respective storage level 130L for transferring case units between anyof the storage spaces 130S of the storage structure 130 (e.g. on thelevel which the bot 110 is located) and any of the lift modules 150(e.g. each of the bots 110 has access to each storage space 130S on arespective level and each lift module 150 on a respective storage level130L). The transfer decks 130B are arranged/arrayed at different levelsand defining multilevel decks (corresponding to each level 130L of thestorage and retrieval system) that may be stacked one over the other orhorizontally offset, such as having one transfer deck 130B at one end orside RMAE1 of the storage rack array RMA or at several ends or sidesRMAE1, RMAE2 of the storage rack array RMA as described in, for example,U.S. patent application Ser. No. 13/326,674 filed on Dec. 15, 2011, thedisclosure of which is incorporated herein by reference in its entirety.

The transfer decks 130B are substantially open and configured for theundeterministic traversal of bots 110 across and along the transferdecks 130B. As may be realized, the transfer deck(s) 130B at eachstorage level 130L communicate with each of the picking aisles 130A onthe respective storage level 130L. Bots 110 bi-directionally traversebetween the transfer deck(s) 130B and picking aisles 130A on eachrespective storage level 130L to access the storage spaces 130S disposedin the rack shelves alongside each of the picking aisles 130A (e.g. bots110 may access storage spaces 130S distributed on both sides of eachaisle such that the bot 110 may have a different facing when traversingeach picking aisle 130A, for example, referring to FIG. 6 , drive wheels202 leading a direction of travel or drive wheels trailing a directionof travel). As noted above, the transfer deck(s) 130B also provide bot110 access to each of the lifts 150 on the respective storage level 130Lwhere the lifts 150 feed and remove case units to and/or from eachstorage level 130L and where the bots 110 effect case unit transferbetween the lifts 150 and the storage spaces 130S. Each storage level130L may also include charging stations 130C for charging an on-boardpower supply of the bots 110 on that storage level 130L such asdescribed in, for example, U.S. patent application Ser. No. 14/209,086filed on Mar. 13, 2014 and Ser. No. 13/326,823 filed on Dec. 15, 2011(now U.S. Pat. No. 9,082,112), the disclosures of which are incorporatedherein by reference in their entireties.

The bots 110 may be any suitable independently operable autonomoustransport vehicles that carry/hold and transfer case units/pickfacesthroughout the storage and retrieval system 100. In one aspect the bots110 are automated, independent (e.g. free riding) autonomous transportvehicles. Suitable examples of bots can be found in, for exemplarypurposes only, U.S. patent application Ser. No. 13/326,674 filed on Dec.15, 2011; U.S. patent application Ser. No. 12/757,312 filed on Apr. 9,2010, (now U.S. Pat. No. 8,425,173); U.S. patent application Ser. No.13/326,423 filed on Dec. 15, 2011; U.S. patent application Ser. No.13/326,447 filed on Dec. 15, 2011, (now U.S. Pat. No. 8,965,619); U.S.patent application Ser. No. 13/326,505 Dec. 15, 2011, (now U.S. Pat. No.8,696,010); U.S. patent application Ser. No. 13/327,040 filed on Dec.15, 2011, (now U.S. Pat. No. 9,187,244); U.S. patent application Ser.No. 13/326,952 filed on Dec. 15, 2011; U.S. patent application Ser. No.13/326,993 filed on Dec. 15, 2011; U.S. patent application Ser. No.14/486,008 filed on Sep. 15, 2014; and U.S. provisional PatentApplication No. 62/107,135 filed on Jan. 23, 2015, the disclosures ofwhich are incorporated by reference herein in their entireties. The bots110 (described in greater detail below) may be configured to place caseunits, such as the above described retail merchandise, into pickingstock in the one or more levels of the storage structure 130 and thenselectively retrieve ordered case units.

The bots 110, lift modules 150 and other suitable features of thestorage and retrieval system 100 are controlled in any suitable mannersuch as by, for example, one or more central system control computers(e.g. control server) 120 through, for example, any suitable network180. In one aspect the network 180 is a wired network, a wirelessnetwork or a combination of wireless and wired networks using anysuitable type and/or number of communication protocols. In one aspect,the control server 120 includes a collection of substantiallyconcurrently running programs (e.g. system management software) forsubstantially automatic control of the automated storage and retrievalsystem 100. The collection of substantially concurrently runningprograms, for example, being configured to manage the storage andretrieval system 100 including, for exemplary purposes only,controlling, scheduling, and monitoring the activities of all activesystem components, managing inventory (e.g. which case units are inputand removed, the order in which the cases are removed and where the caseunits are stored) and pickfaces (e.g. one or more case units that aremovable as a unit and handled as a unit by components of the storage andretrieval system), and interfacing with a warehouse management system2500. The control server 120 may, in one aspect, be configured tocontrol the features of the storage and retrieval system in the mannerdescribed herein. For simplicity and ease of explanation the term “caseunit(s)” is generally used herein for referring to both individual caseunits and pickfaces (formed of multiple case units).

Referring also to FIGS. 1 and 1A the rack module array RMA of thestorage structure 130 includes vertical support members 1212 andhorizontal support members 1200 that define a high density automatedstorage array such as described in, for example, U.S. patent applicationSer. No. 14/997,892, filed on Jan. 18, 2016 and U.S. Provisional PatentApplication No. 62/104,513, filed on Jan. 16, 2015, the disclosures ofwhich are incorporated herein by reference in their entireties. Rails1200S may be mounted to one or more of the vertical and horizontalsupport members 1212, 1200 in, for example, picking aisles 130A and beconfigured so that the bots 110 ride along the rails 1200S through thepicking aisles 130A. At least one side of at least one of the pickingaisles 130A of at least one storage level 130L may have one or morestorage shelves (e.g. formed by rails 1210, 1200 and slats 1210S)provided at differing heights so as to form multiple shelf levels130LS1-130LS2 (although two levels are illustrated any number of levelsmay be provided and the picking aisle can be divided into sections SECA,SECB each having a different number of levels or the same number oflevels) between the storage or deck levels 130L defined by the transferdecks 130B (and the rails 1200S which form an aisle deck). Accordingly,there are multiple rack shelf levels 130LS1-130LS2, corresponding toeach storage level 130L, extending along one or more picking aisles 130Acommunicating with the transfer deck 130B of the respective storagelevel 130L. As may be realized, the multiple rack shelf levels130LS1-130LS2 effect each storage level 130L having stacks of storedcase units (or case layers) that are accessible from a common deck 1200Sof a respective storage level 130L (e.g. the stacks of stored cases arelocated between storage levels). In one aspect, referring to FIG. 1Ceach of the storage levels 130L includes a single level of storageshelves to store a single level of case units (e.g. each storage levelincludes a single case unit support plane CUSP) and the bots 110 areconfigured to transfer case units to and from the storage shelves of therespective storage level 130L.

As may be realized, bots 110 traversing a picking aisle 130A, at acorresponding storage level 130L, have access (e.g. for picking andplacing case units) to each storage space 130S that is available on eachshelf level 130LS1-130LS2, where each shelf level 130LS1-130LS2 islocated between the storage levels 130L on one or more side(s) PAS1,PAS2 (see e.g. FIG. 3A) of the picking aisle 130A. As noted above, eachof the storage shelf levels 130LS1-130LS2 is accessible by the bot 110from the rails 1200S (e.g. from a common picking aisle deck 1200S thatcorresponds with a transfer deck 130B on a respective storage level130L). As can be seen in FIG. 1A there are one or more shelf rails 1210vertically spaced (e.g. in the Z direction) from one another to formmultiple stacked storage spaces 130S each being accessible by the bot110 from the common rails 1200S. As may be realized, the horizontalsupport members 1200 also form shelf rails (in addition to shelf rails1210) on which case units are placed. Here the bots 110 includes atransfer arm 110PA having a vertical drive axis configured to transfercase units to each of the shelf levels 130LS1-130LS2 from the commonpicking aisle deck. A suitable example of bot that services multipleshelf levels from a common picking aisle deck can be found in, forexample, U.S. patent application Ser. No. 14/997,892, filed on Jan. 182016 and U.S. Provisional Patent Application No. 62/104,513 filed onJan. 16, 2015, the disclosures of which are incorporated herein byreference in their entireties. In other aspects, where each storagelevel 130L includes a single level of storage shelves as illustrated inFIG. 1B the bot, such as bot 110′ (which is substantially similar to bot110), is not provided with sufficient Z-travel of the transfer arm 110PAfor placing case units on the multiple storage shelf levels130LS1-130LS2 (e.g. accessible from a common rail 1200S) as describedabove. Here the transfer arm drive of the bots 110′ includes onlysufficient Z-travel for lifting the case units from the case unitsupport plane CUSP of the single level of storage shelves, fortransferring the case units to and from the payload area 110PL and fortransferring the case units between the transfer arm 110PA and thepayload bed 110PB of the payload area 110PL. Suitable examples of bots110′ can be found in, for example, U.S. patent application Ser. No.13/326,993 filed on Dec. 15, 2011, the disclosure of which isincorporated herein by reference in its entirety.

Each stacked shelf level 130LS1-130LS2 (and/or each single shelf level)of a corresponding storage level 130L defines an open andundeterministic two dimensional storage surface (e.g. having a case unitsupport plane CUSP as shown in FIG. 1A) that facilitates a dynamicallocation of pickfaces both longitudinally (i.e. along a length theaisle or coincident with a path of bot travel defined by the pickingaisle) and laterally (i.e. transverse to the aisle or the path of bottravel). Dynamic allocation of the pickfaces and case units that make upthe pickfaces is provided, for example, in the manner described in U.S.Pat. No. 8,594,835 issued on Nov. 26, 2013, the disclosure of which isincorporated by reference herein in its entirety. As such, case unit (ortote) pickfaces of variable lengths and widths are positioned at eachtwo dimensional storage location on the storage shelves (e.g. on eachstorage shelf level 130LS1-130LS2) with minimum gaps (e.g. that effectpicking/placing of case units free from contact with other case unitsstored on the shelves) between adjacent stored case units/storagespaces. In one aspect, the storage space(s) 130S defined by the storageshelf levels 130LS1-130LS4 between the storage or deck levels 130Laccommodates case units of different heights, lengths, widths and/orweights at the different shelf levels 130LS1-130LS2 as described in, forexample, U.S. patent application Ser. No. 14/966,978, filed on Dec. 11,2015 (now U.S. Pat. No. 9,884,719) and U.S. Provisional PatentApplication No. 62/091,162 filed on Dec. 12, 2014, the disclosures ofwhich are incorporated by reference herein in their entireties.

Referring again to FIG. 3A and 3B each transfer deck 130B or storagelevel 130L includes one or more lift interface stations TS where caseunit(s) (of single or combined case pickfaces) or totes are transferredbetween the lift load handling devices LHD and bots 110 on the transferdeck 130B. The interface stations TS (and buffer stations SB describedherein) provide an interface between the bots 110 on a respectivetransfer deck 130B and at least one lift 150 to effect transfer of apickface between the bots 110 and the at least one lift 150. The one ormore lift interface stations TS of one or more of the transfer deck orstorage levels 130L have multi-load stations MLS for positioning and/orbuffering loads CU (such as the case units) for picking by the lifts150B. As described herein, in one aspect, each load is a pickface of oneor more case units picked/placed as a unit at the multi-load station MLSby one or more of the bots 110 and the load handling device(s) LHD oflifts 150B. In one aspect, the case units of each load/pickface aredisposed in a load out as a unit or, in other aspects, are distributedin the load out. As will be described herein, each lift 150 includes acarriage 4001 that has a multi-load platform configured for a commonmulti-load lift/lower so as to, in one aspect, effect a multi-load pick(e.g. from a common interface station TS with a common/single loadhandling device LHD or with multiple independent load handling devicesLHDs) or, in another aspect, effect multiple independent load picks(e.g. such as from interface stations TS at different deck levels) in asingle lift pass. As may be realized, in one aspect, multi-loads (e.g.multiple pickfaces carried together as a single load or unit) arepositioned at one or more of the interface stations TS (or bufferstations BS) for picking by the lifts 150.

The interface stations TS are located at a side of the transfer deck130B opposite the picking aisles 130A and rack modules RM, so that thetransfer deck 130B is interposed between the picking aisles and eachinterface station TS. As noted above, each bot 110 on each picking level130L has access to each storage location 130S, each picking aisle 130Aand each lift 150 on the respective storage level 130L, as such each bot110 also has access to each interface station TS on the respective level130L. In one aspect the interface stations are offset from high speedbot travel paths HSTP along the transfer deck 130B so that bot 110access to the interface stations TS is undeterministic to bot speed on ahigh speed travel path HSTP. As such, each bot 110 can move a caseunit(s) (or pickface, e.g. one or more cases, built by the bot) fromevery interface station TS to every storage space 130S corresponding tothe deck level and vice versa.

In one aspect the interface stations TS are configured for a passivetransfer of case units between the bot 110 and the load handing devicesLHD of the lifts 150 (e.g. the interface stations TS have no movingparts for transporting the case units) which will be described ingreater detail below. For example, also referring to FIG. 3B theinterface stations include one or more stacked levels TL1, TL2 oftransfer rack shelves RTS which in one aspect are substantially similarto the storage shelves described above (e.g. each being formed by rails1210, 1200 and slats 1210S) such that bot 110 handoff (e.g. pick andplace) as well as load handling device LHD handoff (e.g. pick and place)of case units (e.g. individual case units or pickfaces) and totes to thestacked rack shelves RTS (and/or the single level rack shelves) occursin a passive manner substantially similar to that between the bot 110and the storage spaces 130S (as described herein) where the case unitsor totes are transferred to and from the shelves. In other aspects theshelves may include any suitable transfer arms (substantially similar tothe load handling devices LHD of the lifts 150 shown in FIGS. 5A-5E,although Z direction movement may be omitted when the transfer arm isincorporated into the interface station TS shelves) for picking andplacing case units or totes from one or more of the bot 110 and loadhandling device LHD of the lift 150. Suitable examples of an interfacestation with an active transfer arm are described in, for example, U.S.patent application Ser. No. 12/757,354 filed on Apr. 9, 2010, thedisclosure of which is incorporated by reference herein in its entirety.

In one aspect, the location of the bot 110 relative to the interfacestations TS occurs in a manner substantially similar to bot locationrelative to the storage spaces 130S. For example, in one aspect,location of the bot 110 relative to the storage spaces 130S and theinterface stations TS occurs in a manner substantially similar to thatdescribed in U.S. patent application Ser. No. 13/327,035 filed on Dec.15, 2011, (now U.S. Pat. No. 9,008,884) and Ser. No. 13/608,877 filed onSep. 10, 2012, (now U.S. Pat. No. 8,954,188), the disclosures of whichare incorporated herein by reference in their entireties. For example,referring to FIGS. 1 and 1A, the bot 110 includes one or more sensors110S that detect the slats 1210S or a locating feature 130F (such as anaperture, reflective surface, RFID tag, etc.) disposed on/in the rail1200. The slats and/or locating features 130F are arranged so as toidentify a location of the bot 110 within the storage and retrievalsystem, relative to e.g. the storage spaces and/or interface stationsTS. In one aspect the bot 110 includes a controller 110C that, forexample, counts the slats 1210S to at least in part determine a locationof the bot 110 within the storage and retrieval system 100. In otheraspects the location features 130F may be arranged so as to form anabsolute or incremental encoder which when detected by the bot 110provides for a bot 110 location determination within the storage andretrieval system 100.

As may be realized, referring to FIG. 3B, the transfer rack shelves RTSat each interface station TS define the multi-load stations MLS (e.g.having one or more storage case unit holding locations for holding acorresponding number of case units or totes) on a common transfer rackshelf RTS. As noted above, each load of the multi-load station is asingle case unit/tote or a multi-case pickface (e.g. having multiplecase units/totes that are moved as a single unit) that is picked andpaced by either the bot or load handling device LHD. As may also berealized, the bot location described above allows for the bot 110 toposition itself relative to the multi-load stations MLS for picking andplacing the case units/totes and pickfaces from a predetermined one ofthe holding locations of the multi-load station MLS. The interfacestations TS define buffers where inbound and/or outbound caseunits/totes and pickfaces are temporarily stored when being transferredbetween the bots 110 and the load handling devices LHD of the lifts 150.

In one aspect one or more peripheral buffer stations BS (substantiallysimilar to the interface stations) are also located at the side of thetransfer deck 130B opposite the picking aisles 130A and rack modules RM,so that the transfer deck 130B is interposed between the picking aislesand each buffer station BS. The peripheral buffer stations BS areinterspersed between or, in one aspect as shown in FIGS. 3A and 3B,otherwise in line with the interface stations TS. In one aspect theperipheral buffer stations BS are formed by rails 1210, 1200 and slats1210S and are a continuation of (but a separate section of) theinterface stations TS (e.g. the interface stations and the peripheralbuffer stations are formed by common rails 1210, 1200). As such, theperipheral buffer stations BS also include one or more stacked levelsTL1, TL2 of transfer rack shelves RTS as described above with respect tothe interface stations TS. The peripheral buffer stations BS definebuffers where case units/totes and/or pickfaces are temporarily storedfor any suitable reasons such as when being transferred from one bot 110to another different bot 110 on the same storage level 130L. As mayberealized, in one aspect the peripheral buffer stations BS are located atany suitable location of the storage and retrieval system includingwithin the picking aisles 130A and anywhere along the transfer deck130B.

Still referring to FIGS. 3A and 3B in one aspect the interface stationsTS are arranged along the transfer deck 130B in a manner akin to parkingspaces on the side of a road such that the bots 110 “parallel park” at apredetermined interface station TS for transferring case units to andfrom one or more shelves RTS at one or more levels TL1, TL2 of theinterface station TS. In one aspect, a transfer orientation of the bots110 (e.g. when parallel parked) at an interface station TS is the sameorientation as when the bot 110 is travelling along the high speed bottransport path HSTP (e.g. the interface station is substantiallyparallel with a bot travel direction of the transfer deck and/or a sideof the transfer deck on which the lifts 150 are located). Bot 110interface with the peripheral buffer stations BS occurs by parallelparking so that a transfer orientation of the bots 110 (e.g. whenparallel parked) at a peripheral buffer station BS is the sameorientation as when the bot 110 is travelling along the high speed bottransport path HSTP.

In another aspect, referring to FIGS. 4A and 4B, at least the interfacestations TS are located on an extension portion or pier 130BD thatextends from the transfer deck 130B. In one aspect, the pier 130BD issimilar to the picking aisles where the bot 110 travels along rails1200S affixed to horizontal support members 1200 (in a mannersubstantially similar to that described above). In other aspects, thetravel surface of the pier 130BD may be substantially similar to that ofthe transfer deck 130B. Each pier 130BD is located at the side of thetransfer deck 130B, such as a side that is opposite the picking aisles130A and rack modules RM, so that the transfer deck 130B is interposedbetween the picking aisles and each pier 130BD. The pier(s) 130BDextends from the transfer deck at a non-zero angle relative to at leasta portion of the high speed bot transport path HSTP. In other aspectsthe pier(s) 130BD extend from any suitable portion of the transfer deck130B including the ends 130BE1, 130BE2 of the transfer deck 130BD. Asmay be realized, peripheral buffer stations BSD (substantially similarto peripheral buffers stations BS described above) may also be locatedat least along a portion of the pier 130BD.

Referring now to FIGS. 5A, 5B and 5C, as described above, in one aspectthe interface stations TS are passive stations and as such the loadtransfer device LHD of the lifts 150A, 150B have active transfer arms orpick heads 4000A, 4000B. In one aspect the lifts 150 communicatingbetween the input and output conveyors 160CA, 160CB and one or more ofthe interface station(s) TS (which in one aspect include stackedtransfer rack shelves RTS) of the stacked deck levels 130B arereciprocating lifts, e.g. the lifts bi-directionally travel in the Zdirection (relative to a reference frame of the lift as shown in FIG.5C) linearly along a single straight line path. The lifts 150 areunconstrained in their rate of travel in the Z direction and are highspeed lifts (rather than a continuous motion or paternoster type lift)where a transfer rate or speed of the lift is not a delimiting factor inthe transfer of case units to and from the storage and retrieval system.For example, a case unit transfer transaction rate of the lifts 150 issubstantially equal to a case unit transfer transaction rate of the bots110. As may be realized, while the input and output lifts 150A, 150B aredescribed as vertically reciprocating lifts it should be understood thatin other aspects the input and output lifts 150A, 150B are any suitablepickface transport system for transporting case pickfaces to and fromthe storage structure 130. For example, in other aspects the liftmodules 150A, 150B are one or more of vertically reciprocating lifts,any suitable automated material handling systems, conveyors, bots,turntables, roller beds, multilevel vertical conveyor (e.g. paternosterconveyor) that operate synchronously or asynchronously.

As described herein, the lifts 150 traverse and connect more than onelevel 130L of the multilevel transfer decks 130B and are arranged forlifting and lowering a pickface from the multilevel transfer decks 130B.As also described herein, multi-loads placed at, for example, theinterface stations TS are picked with load handling devices LHD of thelifts 150 and transported by the lifts 150 in a single pass/traverse ofthe multiple deck levels 130B to an off load conveyor station, such asoutbound conveyor 160CB. As noted herein, the multi-load pick, in oneaspect, is a common pick from a common interface station TS (effectedwith the common load handling device LHD or by multiple independent loadhandling devices LHD) so that the multi-load pick is effected in onelift stop. In other aspects, the multi-load is picked from differentinterface stations TS at different levels 130L of the multileveltransfer decks 130B, and hence with multiple lift stops, but stillwithin a single pass/traverse of the multiple deck levels (e.g. with nochange in lift travel direction and/or cyclic motion). As will bedescribed further herein, the case loads/pickfaces delivered to theoutput stations 160UT by the lifts 150 are considered to form a caseload stream (e.g. where each lift 150 produces one case load stream).

Referring to, for example, FIGS. 5A-5E, in one aspect, the pick heads(such as pick heads 4000A, 4000B, 4000C, 4000D) of each lift 150 includea multi-load (e.g. multiple pickfaces carried together as a single loador unit) platform (such a load handling device LHD) that is configuredfor a common multi-load lifting/lowering (e.g. relative to, for example,the multiple levels 130L of the storage and retrieval system). In oneaspect, the pick head 4000A, 4000B, 4000C, 4000D effects a multi-loadpick (e.g. from a common interface station with a common/single loadhandling device LHD or with multiple independently operable loadhandling devices LHDs). In another aspect, the pick head 4000A, 4000B,4000C, 4000D effects multiple independent load picks (e.g. such as fromdifferent interface stations TS arranged on difference levels 130L ofthe storage and retrieval system) in a single pass/traverse to an offload conveyor station(s) (e.g. such as outbound conveyors 160CB—FIG. 1 )or any other suitable pickface holding/transport stations. Accordingly,multi-loads are positioned at each or in other aspects, one or more,interface stations TS for picking by the lift 150(s). As may berealized, the multi-load(s) at each or any interface station TS ispicked by a load handling device LHD of the lift 150 and transported bythe lift 150 in a single pass/traversal of the pick head 4000A, 4000Brelative to the levels 130L of the storage and retrieval system to, forexample, the output conveyor 160CB of output station(s) 160UT or othersuitable pickface holding/transport station. As noted above, themulti-load pick is, in one aspect, a common pick from a common interfacestation TS (effected with the common load handling device or by multipleindependent load handling devices LHDs so that the multi-load pickfaceis effected in one stop of the pick head 4000A, 4000B). In otheraspects, the multi-load pick is picked from different interface stationsTS at different level 130L of the storage and retrieval system, andhence multiple stops (but still having with a single pass/traverse—e.g.no change in direction or cyclic motion of the pick head 4000A, 4000B).

In one aspect the inbound lift modules 150A and the outbound liftmodules 150B have different types of pick heads (as will be describedbelow) while in other aspects the inbound lift modules 150A and theoutbound lift modules 150B have the same type of pick head similar toone of the pick heads described below (e.g. both the lifts 150A, 150Bhave pick head 4000A or both lifts 150A, 150B have pick head 4000B). Forexample, both the inbound and outbound lift modules 150A, 150B have avertical mast 4002 (while one mast is illustrated, in other aspectsthere are multiple masts). The vertical mast(s) 4002 spans between abase level BL (FIG. 3B), such as where, for example, the input andoutput conveyors 160CA, 160CB of the input and output stations 160IN,160UT are located, and any desired decks or storage levels 130L of themulti-level storage array. One or more carriage(s) or slide(s) 4001travel along the vertical mast(s) 4002 under the motive force of anysuitable drive unit 4002D (e.g. connected to, for example, controlserver 120) configured to lift and lower the slide (and the pick head4000A, 4000B mounted thereto) between the base level BL and any desiredinterface station shelf at a desired storage level 130L. The drive unit4002D is one or more of a chain drive, a belt drive, a screw drive, alinear actuator, a solid state drive or any other drive capable oflinearly driving the slide(s) and pick heads 4000A, 4000B mountedthereto along the mast(s) 4002.

As may be realized, the lifts 150 include any suitable pick headpositioning system for positioning the pick head(s) 4000A, 4000Brelative to the interface station TS shelves. For example, any suitableencoders or position sensors SENS are provided which, along with controlserver 120, provide for position determination of the pick head(s)4000A, 4000B relative to the interface station TS shelves andinput/output conveyors 160CA, 160CB. For example, the control server 120provides control signals to the lift drives 4002D, 4005, 4005A. Thecontrol server 120 also receives signals from the position sensors SENSas the pick head(s) move along the mast 4002 and determines, based onthe signals a location of the pick heads relative to the interfacestation TS shelves. The control server 120 stops the pick head(s) at apredetermined interface station shelf based on the sensor SENS signalsand effects extension of the load handling device LHD as will bedescribed in greater detail below to pick or place one or more caseunit(s) to the interface station TS shelves.

As noted above, the inbound lift module(s) 150A include a pick head4000A that is movably dependent from the mast(s) 4002, such as by beingmounted to the slide(s) 4001 so that as the slide(s) moves verticallythe pick head 4000A moves vertically with the slide(s) 4001. In thisaspect the pick head 4000A includes a pick head portion or effector LHDAhaving one or more tines or fingers 4273 mounted to a base member 4272so as to form a platform PFM for housing loads. The fingers 4273 areconfigured to pass through or otherwise between the slats 1210S of theinterface stations TS shelves for transferring one or more case unit(s)between the load handling device LHD and the shelves (as will bedescribed in greater detail below). The base member 4272 is movablymounted to one or more rail 4360S of frame 4200 which in turn is mountedto the slide 4001. Any suitable drive unit 4005, such as a belt drive,chain drive, screw drive, gear drive, etc. (which is substantiallysimilar in form but may not be similar in capacity to drive 4002D as thedrive 4005 may be smaller than drive 4002D) is mounted to the frame 4200and coupled to the base member 4272 for driving the base member 4272(with the finger(s), i.e. the effector LHDA) in the direction of arrow4050 (e.g. the Y direction relative to a lift reference frame REFL). Theload platform PFM includes one or more load stations LST1-LST3, eachbeing arranged for holding a case unit(s)/tote or pickface thereon. Inone aspect each platform PFM is illustrated has having three loadstations LST1-LST3 but in other aspects the platforms have more or lessthan three load stations. Each of the case unit(s)/tote or pickface inthe one or more load stations LST1-LST3 is transferred to and from thelift 150 as a unit but it should be understood that where there aremultiple case unit(s)/tote(s) in a load station (e.g. a pickface) thepickface, in one aspect is broken up so that one or more case units thatform the pickface are distributed to a different section of the storagelevel 130L than other case unit(s) of that pickface while in otheraspects the pickface may be placed within a storage space 130S as a unitin the manner described, for example, in U.S. patent application Ser.No. 14/997,892, filed on Jan. 18, 2016 and U.S. Provisional PatentApplication No. 62,104,513 filed on Jan. 16, 2015, the disclosures ofwhich were previously incorporated herein by reference in theirentireties.

The outbound lift module(s) 150B also include a pick head 4000B mountedto the slide 4001 so that as the slide moves vertically the pick head4000B moves vertically with the slide 4001. In this aspect the pick head4000B includes one or more pick head portions or effectors LHDA, LHDB(which are each substantially similar to pick head 400A) each having oneor more tines or fingers 4273 mounted to a respective base member 4272A.Each base member 4272A is movably mounted to one or more rail 4360SA offrame 4200A which in turn is mounted to the slide 4001. Any suitabledrive unit(s) 4005A, such as a belt drive, chain drive, screw drive,gear drive, etc. is mounted to the frame 4200A and coupled to arespective base member 4272A for driving the respective base member4272A (with the finger(s)) in the direction of arrow 4050 (each effectorhas a respective drive unit so that each effector is independentlymovable in the direction of arrow 4050). While two effectors LHDA, LHDBare illustrated on pick head 4000B the pick head 4000B includes anysuitable number of effectors that correspond to a number of caseunit/pickface holding locations of, for example, the interface stationsTS so that case units/pickfaces are individually picked from theinterface stations TS are described in greater detail below.

In one aspect, referring also to FIG. 5D, one or more of the input andoutput lifts 150 includes multiple pick heads 4000C, 4000D each mountedto a corresponding carriage or slide 4001A, 4001B. Each of the slides4001A, 4001B (and the pick head mounted thereto) is mounted to the mast4002 so as to be independently moveable in the Z direction by arespective drive 4002DA, 4002DB (which is substantially similar to drive4002D described above). While each pick head 4000C, 4000D illustrated inFIG. 5D includes a single load handling device it should be understoodthat one or more of the pick heads, in other aspects, 4000C, 4000Dincludes multiple independently actuated load handling devices in amanner similar to pick head 4000B. As may also be realized, suitableclearance is provided between each of the slides 4001A, 4001B and thepick head(s) mounted thereto so that each pick head is provided with thefull stroke of travel (e.g. from the base level BL (FIG. 3A) to, forexample, the interface station shelves at the top storage level 130L)along the mast 4002 as desired.

In another aspect each load handling device LHD, as described above, ofthe lifts 150A, 150B is configured to sort one or more case unitsonboard the load handling device for building pickfaces on the loadhandling device. For example, referring to FIG. 5E the carriage 4200Bincludes a frame 4110F having a payload section 4110PL. The payloadsection 4110PL of the load handling device LHD includes a payload bed4110PB, a fence or datum member 4110PF, a transfer arm LHDA and a pusherbar or member 4110PR. In one aspect the payload bed 4110PB includes oneor more rollers 4110RL that are mounted to the frame 110F so as to besubstantially parallel with the fingers 4273A-4273E where one or morecase units carried within the payload section 110PL can be moved in theX direction (e.g. justified with respect to a predetermined location ofthe frame/payload section and/or a datum reference of one or more caseunits in the lift frame of reference REFL) to position the case unit ata predetermined position within the payload section 4110PL and/orrelative to other case units within the payload section 4110PL (e.g.side to side justification of case units as opposed to fore/aft asdefined by the direction of extension of the transfer arm LHDA asdescribed below, e.g. in the Y direction relative to the lift frame ofreference). In one aspect the rollers 4110RL may be driven (e.g. rotatedabout their respective axes) by any suitable motor for moving the caseunits within the payload section 4110PL. In other aspects the loadhandling device LHD includes one or more side justification movablepusher bar (not shown) for pushing the case units over the rollers4110RL for moving the case unit(s) to the predetermined position withinthe payload section 4110PL along the X direction. The side justificationmovable pusher bar may be substantially similar to that described in,for example, U.S. patent application Ser. No. 13/326,952 filed on Dec.15, 2011, the disclosure of which was previously incorporated byreference herein in its entirety. The pusher bar 4110PR is movable inthe Y direction, relative to the lift reference frame REFL to effect,along with the fence 4110PF and or pick head 4270 of the transfer armLDHA, a fore/aft justification of case unit(s) within the payload area4110PL in the manner described in U.S. Provisional Patent ApplicationNo. 62/107,135 filed on Jan. 23, 2015, previously incorporated herein byreference in their entireties.

Still referring to FIG. 5E, the case units are placed on the payload bed4110PB and removed from the payload bed 4110PB with the transfer armLHDA. The transfer arm LHDA includes a lift mechanism or unit 5000located substantially within the payload section 4110PL as described in,for example, U.S. Provisional Patent Application No. 62/107,135 filed onJan. 23, 2015, previously incorporated herein by reference in theirentireties. The lift mechanism 5000 provides, in addition to or in lieuof movement of the carriage 4200B in the Z direction, both gross andfine positioning of pickfaces carried by the load handling device LHDwhich are to be lifted vertically into position in the storage structure130 for picking and/or placing the pickfaces and/or individual caseunits to and from the shelves of the interface stations TS.

The lift mechanism 5000 is configured so that combined axis moves areperformed (e.g. combined substantially simultaneous movement of thepusher bar 4110PR, lift mechanism 5000, pick head extension and fore/aftjustification mechanism(s)), so that different/multi-sku or multi-pickpayloads are handled by the lift 150. In one aspect, the actuation ofthe lifting mechanism 5000 is independent of actuation of the pusher bar4110PR as will be described below. The decoupling of the lift mechanism5000 and pusher bar 4110PR axes provides for combined pick/placesequences effecting a decreased pick/place cycle time, increased storageand retrieval system throughput and/or increased storage density of thestorage and retrieval system as described above. For example, the liftmechanism 5000 provides for lifting case units from the payload bed4110PL of the load handling device LHD to allow for sorting andjustifying case units to predetermined positions on the payload bed41110PL and thus on the transfer arm LHDA. In one aspect the case unitsare lowered on the payload bed if sorting or justification is desired,otherwise the transfer arm LHDA may remain at least partially lifted toallow the arm to extend and retract for picking/placing case unitsto/from the interface stations TS without a secondary lifting of thetransfer arm LHDA above the fence 4110PF in addition to, for example,traversal of the load handling device LHD along the mast(s) 4002.

The lifting mechanism 5000 may be configured in any suitable manner sothat a pick head 4270 of the load handling device LHD bi-directionally(e.g. reciprocates) moves along the Z axis (e.g. in the Z direction). Inone aspect, the lifting mechanism 5000 includes a mast 5000M and thepick head 4270 is movably mounted to the mast 4200M in any suitablemanner. The mast 4200M is movably mounted to the frame 4110F in anysuitable manner so as to be movable along the Y direction. In one aspectthe frame includes guide rails 4360S to which the mast 4200M is slidablymounted. A transfer arm drive 4005 may be mounted to the frame foreffecting at least movement of the transfer arm LHDA along the Ydirection and the Z direction. In one aspect the transfer arm drive 4005includes an extension motor 4301 and a lift motor 4302. The extensionmotor 4301 may be mounted to the frame 4110F and coupled to the mast4200M in any suitable manner such as by a belt and pulley transmission4260A, a screw drive transmission (not shown) and/or a gear drivetransmission (not shown). The lift motor 4302 may be mounted to the mast4200M and coupled to pick head 4270 by any suitable transmission, suchas by a belt and pulley transmission 4271, a screw drive transmission(not shown) and/or a gear drive transmission (not shown). As an example,the mast 4200M includes guides, such as guide rails 4280, along whichthe pick head 4270 is mounted for guided movement in the Z directionalong the guide rails 4280. In other aspects the pick head 4270 ismounted to the mast in any suitable manner for guided movement in the Zdirection. With respect to the transmissions In other aspects anysuitable linear actuators are used to move the pick head in the Zdirection. The transmission 260A for the extension motor 301 issubstantially similar to that described herein with respect totransmission 271.

Still referring to FIG. 5E the pick head 4270 of the load handlingdevice LHD transfers case units between the load handling device LHD andinterface stations TS (see e.g. FIG. 3A) and in other aspectssubstantially directly between the bot 110 and a lift module(s) 150. Inone aspect, the pick head 4270 includes a base member 4200B1, one ormore tines or fingers 4273A-4273E and one or more actuators 4274A,4274B. The base member 4200B1 is mounted to the mast 4200M, as describedabove, so as to ride along the guide rails 4280. The one or more tines4273A-4273E are mounted to the base member 4200B1 at a proximate end ofthe tines 4273A-4273E so that a distal end of the tines 4273A-4273E(e.g. a free end) is cantilevered from the base member 4200B1. Referringagain to FIG. 1A, the tines 4273A-4273E are configured for insertionbetween slats 1210S that form the case unit support plane CUSP of theinterface station TS shelves.

One or more of the tines 4273A-4273E is movably mounted to the basemember 4200B1 (such as on a slide/guide rail similar to that describedabove) so as to be movable in the Z direction. In one aspect any numberof tines are mounted to the base member 4200B1 while in the aspectillustrated in the figures there are, for example, five tines4273A-4273E mounted to the base member 4200B1. Any number of the tines4273A-4273E are movably mounted to the base member 4200B1 while in theaspect illustrated in the figures, for example, the outermost (withrespect to a centerline CL of the pick head 4270) tines 4273A, 4273E aremovably mounted to the base member 4200B1 while the remaining tines4273B-4273D are immovable relative to the base member 4200B1.

In this aspect the pick head 4270 employs as few as three tines4273B-4273D to transfer smaller sized case units (and/or groups of caseunits) to and from the load handling device LHD and as many as fivetines 4273A-4273E to transfer larger sized case units (and/or groups ofcase units) to and from the load handling device LHD. In other aspects,less than three tines are employed (e.g. such as where more than twotines are movably mounted to the base member 4200B1) to transfer smallersized case units. For example, in one aspect all but one tine4273A-4273E is movably mounted to the base member 4200B1 so that thesmallest case unit being transferred to and from the load handlingdevice without disturbing other case units on, for example, the shelvesof the interface stations has a width of about the distance X1 betweenslats 1210S (see FIG. 1A).

The immovable tines 4273B-4273D define a picking plane SP of the pickhead 4270 and are used when transferring all sizes of case units (and/orpickfaces) while the movable tines 4273A, 4273E are selectively raisedand lowered (e.g. in the Z direction with the actuators 274A, 274B)relative to the immovable tines 4273B-4273D to transfer larger caseunits (and/or pickfaces). Still referring to FIG. 5E an example is shownwhere all of the tines 4273A-4273E are positioned so that a case unitsupport surface SF of each tine 4273A-4273E is coincident with thepicking plane SP of the pick head 4270 however, as may be realized, thetwo end tines 4273A, 4273E are movable so as to be positioned lower(e.g. in the Z direction) relative to the other tines 4273B-4273D sothat the case unit support surface SF of tines 4273A, 4273E is offsetfrom (e.g. below) the picking plane SP so that the tines 4273A, 4273E donot contact the one or more case units carried by the pick head 4270 anddo not interfere with any unpicked case units positioned inpredetermined case unit holding locations on the interface station TSshelves.

The movement of the tines 4273A-4273E in the Z direction is effected bythe one or more actuators 4274A, 4274B mounted at any suitable locationof the transfer arm LHDA. In one aspect, the one or more actuators4274A, 4274B are mounted to the base member 4200B1 of the pick head4270. The one or more actuators are any suitable actuators, such aslinear actuators, capable of moving one or more tines 4273A-4273E in theZ direction. In the aspect illustrated in, for example, FIG. 5E there isone actuator 4274A, 4274B for each of the movable tines 4273A, 4273E sothat each moveable tine is independently movable in the Z direction. Inother aspects one actuator may be coupled to more than one movable tineso that the more than one movable tine move as a unit in the Zdirection.

As may be realized, movably mounting one or more tines 4273A-4273E onthe base member 4200B1 of the pick head 4270 provides for full supportof large case units and/or pickfaces on the pick head 4270 while alsoproviding the ability to pick and place small case units withoutinterfering with other case units positioned on, for example, theshelves of interface stations TS. The ability to pick and place variablysized case units without interfering with other case units at theinterface stations reduces a size of a gap G (FIG. 6 ) between caseunits on the interface stations shelves

Referring again to FIG. 5E, it is again noted that the pusher bar 4110PRis movable independent of the transfer arm LHDA. The pusher bar 4110PRis movably mounted to the frame 4110F in any suitable manner such as by,for example, a guide rod and slide arrangement and is actuated along theY direction (e.g. in a direction substantially parallel to theextension/retraction direction of the transfer arm LHDA). In one aspectat least one guide rod 4360 is mounted within the payload section 4110PLfor guiding movement of the pusher 4110PR in the Y direction. In oneaspect, at least the guide rod/slide arrangement holds the pusher bar4110PR captive within the payload section 4110PL. The pusher bar 4110PRis actuated by any suitable motor and transmission, such as by motor4303 and transmission 4303T. In one aspect the motor 4303 is a rotarymotor and the transmission 4303T is a belt and pulley transmission. Inother aspects the pusher bar 110PR may be actuated by a linear actuatorhaving substantially no rotary components.

The pusher bar 4110PR is arranged within the payload section 4110PL soas to be substantially perpendicular to the rollers 4110RL and so thatthe pusher bar 4110PR does not interfere with the pick head 4270 (thepusher bar 4110PR includes slots 4351 into which the fingers 4273A-4273Epass when lowered into the payload bed 4110PB where the slots 4351 aresized to allow unhindered movement of the pusher bar relative to thefingers 4273A-4273E). The pusher bar 4110PR also includes one or moreapertures through which the rollers 4110RL pass where the apertures aresized to allow free rotation of the rollers about their respective axes.As may be realized, the independently operable pusher bar 4110PR doesnot interfere with the rollers 4110PR, extension of the transfer armLHDA in the transverse direction (e.g. Y direction) and thelifting/lowering of the pick head 4270.

As may be realized, the lift modules 150A, 150B are under the control ofany suitable controller, such as control server 120, such that whenpicking and placing case unit(s) the pick head is raised and/or loweredto a predetermined height corresponding to a shelf of an interfacestation TS at a predetermined storage level 130L. At the interfacestations TS the pick head 4000A, 4000B, 4270 or individual portionthereof (e.g. effector LHDA, LHDB), corresponding to one or more caseunit holding location(s) of the interface station TS from which one ormore case unit(s) are being picked, is extended so that the fingers 4273are interdigitated between the slats 1210S (as illustrated in FIG. 5B)underneath the case unit(s) being picked. The lift 150A, 150B raises thepick head 4000A, 4000B, 4270 to lift the case unit(s) from the slats1210S and retracts the pick head 4000A, 4000B, 4270 for transport of thecase unit(s) to another level of the storage and retrieval system, suchas for transporting the case unit(s) to output station 160UT. Similarly,to place one or more case unit(s) the pick head 4000A, 4000B, 4270 orindividual portion thereof (e.g. effector LHDA, LHDB), corresponding toone or more case unit holding location(s) of the interface station TSfrom which one or more case unit(s) are being placed, is extended sothat the fingers 4273 are above the slats. The lift 150A, 150B lowersthe pick head 4000A, 4000B, 4270 to place the case unit(s) on the slats1210S and so that the fingers 4273 are interdigitated between the slats1210S underneath the case unit(s) being picked.

An example of a lift 150 case unit(s) transfer transaction including acase unit(s) multi-pick and place operation and on the fly sortation ofthe case units for creating a mixed pallet load MPL (as shown in FIG. 2) according to a predetermined order/load out sequence and/or in thepredetermined order sequence (e.g. an order/load out sequence) of pickeditems according to, for example, an order, fulfilling one or morecustomer orders, in which case units CU are sequenced for placement inone or more bag(s), tote(s) or other container(s) TOT at an operatorstation 160EP (as shown in FIG. 14 ) as will be described with respectto FIGS. 5A-5E, 6 and 7-7E in accordance with aspects of the disclosedembodiment. In one aspect, the control server 120 is configured to oneor more of command the bot 110, and effect with the bot 110 outboundflow (e.g. fulfillment stream) sortation of case order(s) independent ofthe pick order of cases from the storage area by the bot 110 forming apickface (as described in U.S. patent application Ser. No. 14/997,892,filed on Jan. 18, 2016, previously incorporated by reference herein byreference), and command the lift(s) 150 and effect with the lift(s) 150outbound flow (e.g. fulfillment stream) sortation of case ordersindependent of the order in which the case units were placed at, forexample the transfer station(s) TS (or buffer stations BS) by the bot110 (as described in U.S. patent application Ser. No. 14/997,902, filedon Jan. 18, 2016, previously incorporated herein by reference). In oneaspect, the bot controller 110C is configured to command the bot 110,and effect with the bot 110 outbound flow sortation of case order(s)independent of the pick order of cases from the storage area by the bot110 forming a pickface. In still other aspects, the control server 120and the bot controller 110C are both configured to command the bot 110,and effect with the bot 110 outbound flow sortation of case order(s)independent of the pick order of cases from the storage area by the bot110 forming a pickface. Thus, in one aspect, the control server 120and/or the bot controller 110C is/are configured to set the outboundcase flow, at least in part with bot 110 sortation of the cases carriedin common by the bot 110 and decoupled from the pick order of the casesby the bot 110 from storage. This may be referred to for descriptionpurposes as outbound flow sortation with the bot at transfer stations(and/or at buffer stations). In another aspect, the control server 120and/or the lift(s) 150 is/are configured to set the outbound case flow,at least in part with lift 150 sortation of the cases carried in commonby the lift 150 and decoupled from the pick order of the cases by thelift from the transfer stations TS (or buffer stations BS). This may bereferred to for description purposes as outbound flow sortation with thelift at transfer stations (and/or at buffer stations).

In one aspect, multiple transfer decks 130B are provided and arrayed atdifferent levels so as to define multilevel decks in the mannerdescribed above (FIG. 6A, Block 900). One or more bots 110 are disposedon each of the multilevel decks 130B, as described above, for holdingand transporting pickfaces on each deck 130B (FIG. 6A, Block 910). Thepickfaces are lifted and/or lowered from the multilevel decks 130B inaccordance with a load out sequence, in a manner substantially similarto that described below, with at least one outbound lift 150B thattraverses and connects more than one level of the multilevel decks 130B(FIG. 6A, Block 920). As may be realized, each load out (truck load,pallet load, etc. filled with cases from the storage and retrievalsystem 100) from the distribution center or warehouse, e.g. in which thestorage and retrieval system 100 is located, has a predeterminedsequence or order of caseloads (of single cases or combined cases) inwhich the case loads are integrated to fill the load out (e.g. the loadout order sequence which is defined in any suitable manner such as thatdescribed in U.S. patent application Ser. No. 13/654,293 filed on Oct.17, 2012 (now U.S. Pat. No. 8,965,559), previously incorporated hereinby reference in its entirety, and/or a rules based system that is basedon customer criteria, off load criteria or any other suitable criteria.As will be described below, transfer of the pickfaces (e.g. case loads)between the bot 110 and the at least one outbound lift 150B is effectedwith at least one transfer station TS (or buffer station BS) on eachdeck that interfaces between the bot 110 on a respective transfer deck130B and the at least one outbound lift 150B (FIG. 6A, Block 930). Inone aspect, each outbound lift 150B defines at least one case loadstream of an order fulfillment stream (which may also be referred to asan outbound stream/flow or order fulfillment) that includes mixed casepickfaces outbound from the multilevel decks 130B to a load out fill orload fill where at least one case load stream of the fulfillment streamis arranged in an ordered sequence of streaming pickfaces related to thepredetermined sequence of the load out fill (e.g. the individual caseload streams of the lifts 150B form an order fulfillment streamcorresponding to the load out fill) (FIG. 6A, Block 940). As may berealized, the at least one transfer station TS (or buffer station BS) onat least one of the multilevel decks commonly supports more than one ofthe mixed case pickfaces (e.g. that define a portion of the streamingpickfaces in the ordered sequence of streaming pickfaces) based on, forexample, a predetermined sequence of the load out fill. In one aspectthe interface station TS (or buffer station BS) forms a common pickfacetransfer interface for the at least one outbound lift 150B, so that thecommonly supported pickfaces are picked in common with the at least oneoutbound lift 150B. In one aspect, the interface stations TS (or bufferstations BS) commonly support more than one of the mixed case pickfacesin an ordered sequence based on the predetermined sequence of the loadout fill. As may be realized, any suitable controller, such ascontroller 120 is in communication with the one or more bots 110 and isconfigured to effect placement of pickfaces on the at least one transferstation TS (or buffer station BS) based on the ordered sequence ofstreaming pickfaces. In one aspect the ordered sequence of streamingpickfaces is based on another fulfillment stream of, for example,another outbound lift 150B. As may be realized, if there is more thanone case load stream (e.g. from multiple outbound lifts 150B), the caseloads of each case load stream are in a corresponding order sequencerelated to the predetermined sequence of the load out fill, as well asto each other, to provide a coordinated and harmonized integration ofthe case loads in each stream in the load out fill (e.g. the individualcase load streams are combined according to the predetermined sequenceof the load out fill to form the order fulfillment stream where thefirst ordered sequence of streaming pickfaces from a first liftcomplements the second ordered sequence of streaming pickfaces from asecond lift) (FIG. 6A, Block 950). In one aspect, the ordered sequenceof the case loads in each case load stream is defined by the orderedsequence of the multi-case loads of each load out (e.g. outbound) strokeof the outbound lift 150B generating/feeding the case load stream (e.g.see FIG. 1B where the sequencing 174 is performed by the vertical casetransport 173 of the outbound lifts 150B). In one aspect, thefulfillment stream sortation for each sortation system/method, asdescribed herein, is based, at the sortation itself, on anotherfulfillment stream so that the sortation with the bot 110 at thetransfer station TS (or buffer station BS) is dependent on a sequence ofanother fulfillment stream (such as by another bot at the same or adifferent transfer station TS), and the sortation by the lift 150 isdependent on another fulfillment stream (such as by another lift 150).

As an example, of case load streams, referring to FIG. 6 , there are twooutbound lifts 150B1, 150B2, each lift having a respective case loadstream COS1, COS2 which is transferred to the outbound conveyors 160CBthrough transfer stations 160TS, 160TSA (in other aspects there is anysuitable number of outbound lifts with any suitable corresponding numberof case load streams being provided to a load out fill). For example,the ordered sequence of the case loads in each case load stream COS1,COS2 is defined by the ordered sequence of the multi-caseloads of eachload out (outbound) stroke of the respective lift 150B1, 150B2generating/feeding the case load stream COS1, COS2 (e.g. the multi-loadsof each lift load out stroke are arranged in the ordered sequencerelated to the fill sequence). Here the order fulfillment stream isdefined by the two lifts 150B1, 15B2 however, in other aspects the orderfulfillment stream is defined by one of the lifts 150B1, 150B2independent of other ones of the lifts 150B1, 150B2.

In one aspect, the sorting of the multi-loads to the ordered/fillsequence is effected both prior to lift pick and/or during lift pick.For example, sorting prior to lift pick includes case units/pickfaces(e.g. multi-case loads) being delivered by the bots 110 to interfacestation shelves 7000A-7000L of the transfer stations TS of the differenttransfer deck levels 130B. In one aspect the case load delivery timingof the case loads by the bots 110 to the transfer stations TS is not insequence however, the case loads delivered correspond to thepredetermined sequence of the case load stream COS1, COS2 output by therespective outbound lift 150B1, 150B2 for effecting the ordered fillsequence. For example, the multi-case loads are placed on the interfacestations TS (of one or more deck levels) in a sorted arrangement (eventhough the delivery timing is not in sequence) so as to be in an orderedsequence (e.g. at least the case units needed for the ordered sequenceare placed on the interface stations TS in a known relationship with therespective interface stations TS) per the load out fill sequence. Aswill be described below, in one aspect, the lift 150 picks themulti-case loads from the interface stations TS located at one or moredeck levels to feed the respective case load stream COS1, COS2. In oneaspect the load out fill sequence of each lift 150B is consecutive (n)(e.g. such as where a single stream COS1, COS2 forms the load out fill)or a consecutive skip sequence (n+i where i=1 to m and i corresponds tothe number of load streams COS1, COS2 integrated to the load out fill)where there are multiple streams COS1, COS2 forming the load out fill.In the latter case, the ordered sequence of each lift interface stationTS (or buffer station BS) is matched or related to the ordered sequenceof other load streams converging to the load out fill.

As an example, FIG. 6 illustrates a load out fill in which two case loadstreams COS1, COS2 are integrated to form a load out fill for a customerorder. Here at least one of the case load streams COS1, COS2 are relatedto the predetermined pickface load order sequence for the load out fill.For exemplary purposes, the customer order may require case unit(s) 1-8which are provided by the two lifts 150B1, 150B2. Here case units 1 and3 are output by the lift 150B1 in case load stream COS1 while case units2 and 4 are output to case load stream COS2 so that the cases arrive atthe output station 160US in an alternating manner defined by the orderedsequence of the fulfillment stream. In accordance with the orderedsequence case loads 7 and 5 are to be delivered to output conveyor 160CBsuch that case units are carried and transferred by a common loadhandling device LHD of lift 150B1 from different holding locations ofone or more interface station shelves 7000A-7000F in a single pass ofthe stack of interface stations TS. To efficiently use each lift 150 inthe storage and retrieval system 100 the controller, such as controlserver 120, determines on which interface stations(s) case units 5, 7are located. The controller sends commands to a lift, such as lift 150B1associated with the interface stations TS where case units 5, 7 arelocated to pick one or more of the outbound case units.

In one aspect where the lift 150B1 picks case units 5, 7 from a commonshelf 7000B of an interface station TS the lift 150B1 moves one or moreload handling devices LHD, LHD1, LHD2 of the lift (and the pick head4000A, 4000B, 4000C, 4000D, 4270 thereon) in the Z direction so that thetransfer arm LHDA, LHDB is located substantially at a level of theinterface station shelf 7000B (FIG. 8 , Block 11000). The transfer armLHDA, LHDB of the one or more load handling devices LHD, LHD1, LHD2 isextended (e.g. extension of a common transfer arm as in FIG. 5A or thesubstantially simultaneous extension of two transfer arms as in FIGS. 5Cand 5D) in the Y direction so that the fingers 4273 are disposed betweenthe slats 1210S below the case units 5, 7 (FIG. 8 , Block 11010). Thelift 150B1 moves the one or more load handling devices LHD, LHD1, LHD2in the Z direction so that the fingers 4273 pass through the slats 1210Sto lift/pick the case units 5, 7 from the interface station shelf 7000B(FIG. 8 , Block 11020). The transfer arm LHDA, LHDB is retracted in theY direction so as to place the case units 5, 7 within a transfer columnTC (e.g. an area of open space in which the load handling device travelsalong the Z direction free from interference from the interface stationsand outbound conveyors) of the lift 150B1 (FIG. 8 , Block 11030). Thelift 150B1 moves the one or more load handling devices LHD, LHD1, LHD2in the Z direction so that the transfer arm LHDA, LHDB is locatedsubstantially at a level of an interface station 160TS of the conveyor160CB (FIG. 8 , Block 11040). The transfer arm LHDA, LHDB of the one ormore load handling devices LHD, LHD1, LHD2 is extended in the Ydirection so as to place the case units 5, 7 substantially above theinterface station 160TS (FIG. 8 , Block 11050) and the lift 150B1 movesthe one or more load handling devices LHD, LHD1, LHD2 in the Z directionso that the fingers 4273 pass through the slats of the interface station160TS (in a manner similar to that illustrated in FIG. 5B) tolower/place the case units 5, 7 on a shelf of the interface station160TS (FIG. 8 , Block 11060). The transfer arm LHDA, LHDB is retractedin the Y direction so as to place the transfer arm LHDA, LHDB within thetransfer column TC of the lift 150B1 (FIG. 8 , Block 11070). Here caseunits carried at all load stations LST1-LST3 (e.g. case unit holdinglocations) of a common platform PFM (e.g. as in FIG. 5A and as in FIGS.5C, 5D where the simultaneous extension/retraction of transfer armsLHDA, LHDB effects a common platform) are picked, transferred and placedin unison with the lift platform at a common elevation. Case units 6, 8are transferred to the outbound conveyors 160CB by the lift 150B1 in amanner substantially similar to that described above with respect to thetransfer of case units 5, 7 by lift 150B1. As may be realized, the loadfill formed by the case load streams COS1, COS2 include mixed casepickfaces arranged in a predetermined pickface load order sequence. Inone aspect, the ordered sequence of streaming pickfaces 1, 3, 5, 7 (e.g.case load stream COS1) is combined with a pickface 2, 4, 6, 8 from theother case load stream COS2 to fill the load fill in the predeterminedpickface load order sequence 1, 2, 3, 4, 5, 6, 7, 8. In one aspect, atleast one pickface from the other case load stream COS2 in combinationwith the ordered sequence of streaming pickfaces from the case loadstream COS1 forms a portion of consecutive ordered pickfaces (e.g.pickfaces 1, 2, 3, 4, . . . as shown in FIG. 6 ) of the predeterminedpickface load order sequence.

In one aspect, as noted above, the lift 150 sorts the multi-load caseswhen picking the multi-load cases from interface stations TS located asdifferent deck levels where the sorting sequence corresponds to theordered sequence of streaming pickfaces (e.g. case load streams COS1,COS2). For example, a multiple transfer arm load handling device LHD asin FIG. 5C (and also the individually operable load handling devicesLHD1, LHD2 of FIG. 5D) picks and places case units from more than oneinterface station TS at different storage levels 130LA, 130LB andtransfers the case units to the same or different outbound conveyortransfer stations TS (e.g. such as when the transfer stations TS of oneor more the outbound conveyors serving a common lift 150 are stacked oneabove the other). For exemplary purposes only, a customer order mayrequire case units 5, 7 to be delivered to conveyor 160CB. Again, toefficiently use each lift 150 in the storage and retrieval system 100the controller, such as control server 120, determines on whichinterface stations(s) case units 5, 7 are located. The controller sendscommands to a lift, such as lift 150B1 associated with the interfacestations TS where case units 5, 7 are located to pick one or more of theoutbound case units in a single pass of the load handling device LHD.Here, case units 5, 7 are located on different shelves 7000A-7000F ofdifferent interface stations TS such that the lift 150B1 moves one ormore load handling devices LHD, LHD1, LHD2 of the lift (and the pickhead 4000A, 4000B, 4000C, 4000D, 4270 thereon) in the Z direction sothat the transfer arm LHDA, LHDB is located substantially at a level130LA, 130LB of one of the interface station shelves 7000B, 7000D (FIG.9 , Block 12000). The transfer arm LHDA, LHDB of the one or more loadhandling devices LHD, LHD1, LHD2 is extended in the Y direction so thatthe fingers 4273 are disposed between the slats 1210S below one of thecase units 5, 7 (FIG. 9 , Block 12010) such as case unit 7 when caseunit 7 is being picked on an upstroke of the lift 150B before pickingcase unit 5 or case unit 5 when case unit 5 is being picked on a downstroke of the lift 150B before picking case unit 7. The lift 150B1 movesthe one or more load handling devices LHD, LHD1, LHD2 in the Z directionso that the fingers 4273 pass through the slats 1210S to lift/pick oneof the case units 5, 7 (which is some aspects may be a pickfaceincluding more than one case unit) from the interface station shelf7000B (FIG. 9 , Block 12020). The transfer arm LHDA, LHDB is retractedin the Y direction so as to place the case units 5, 7 within a transfercolumn TC (e.g. an area of open space in which the load handling devicetravels along the Z direction free from interference from the interfacestations and outbound conveyors) of the lift 150B1 (FIG. 9 , Block12030). The lift 150B1 moves the one or more load handling devices LHD,LHD1, LHD2 in the Z direction so that the transfer arm LHDA, LHDB islocated substantially at a level of interface station shelf 7000A, 7000Bwhere the other case unit 5, 7 is located (FIG. 9 , Block 12035) forpicking the other case unit in the manner described above (FIG. 9 ,Blocks 12010, 12020, 12030). The lift 150B1 moves the one or more loadhandling devices LHD, LHD1, LHD2 in the Z direction so that the transferarm LHDA, LHDB is located substantially at a level of an interfacestation 160TS of the conveyor 160CB (FIG. 9 , Block 12035). The transferarm LHDA, LHDB of the one or more load handling devices LHD, LHD1, LHD2is extended in the Y direction so as to place the case units 5, 7substantially above the interface station 160TS (FIG. 9 , Block 12050)and the lift 150B1 moves the one or more load handling devices LHD,LHD1, LHD2 in the Z direction so that the fingers 4273 pass through theslats of the interface station 160TS (in a manner similar to thatillustrated in FIG. 5B) to lower/place the case units 5, 7 on a shelf ofthe interface station 160TS (FIG. 9 , Block 12060). In one aspect thecase units 5, 7 are placed on the interface station 160TS substantiallysimultaneously as a unit while in other aspects the case units 5, 7 areplaced on the interface station 160TS sequentially at different times,such as one after another and/or placed to different outbound conveyorsinterface stations 160TS (e.g. such as when the transfer stations TS ofone or more the outbound conveyors serving a common lift 150 are stackedone above the other) according to a predetermined order out sequence forbuilding the mixed pallet MPL (FIG. 2 ). The transfer arm LHDA, LHDB isretracted in the Y direction so as to place the transfer arm LHDA, LHDBwithin the transfer column TC of the lift 150B1 (FIG. 9 , Block 12070).

In one aspect a common load handling device LHD, LHD1, LHD2 isconfigured to pick/place one or more case units from multiple interfacestation TS shelves with a common transfer arm where the case units aresorted on the fly (e.g. during transport on the lift) and/or justifiedon the load handling device LHD, LHD1, LHD2. For example, the outboundcase units 5, 7 are located on interface station shelves 7000B, 7000D ofdifferent storage levels 130LA, 130LB. Again, to efficiently use eachlift 150 in the storage and retrieval system 100 the controller, such ascontrol server 120, determines on which interface stations(s) case units5, 7 are located. The controller sends commands to a lift, such as lift150B1 associated with the interface stations TS where case units 5, 7are located to pick one or more of the outbound case units in a singlepass of the load handling device LHD. Here For example, referring toFIGS. 6, 7 and 7A-7E the load handling device LHD, LHD1, LHD2 of lift150B1 picks case unit 7 (which may be a pickface of more than one caseunit) from interface station shelf 7000B in the manner described above(FIG. 10 , Block 13000). The case unit(s) 7 is justified on the loadhandling device towards the rear of the payload section 4110PL as willbe described in greater detail below (FIG. 10 , Block 13005). The loadhandling device LHD, LHD1, LHD2 continues to travel along the mast 4002in a common pass of the vertical stack of interface stations TS andpicks case unit 5 from a different interface station shelf 7000D withthe common transfer arm LHDA so that both case unit(s) 7, 5 are locatedadjacent one another on the common transfer arm LHDA (FIG. 10 , Block13010). As may be realized, in one aspect, the controller 120 isconfigured to effect picking of the case unit(s) 5, 7 in any suitableorder such as, for example, an order that is opposite an order in whichthe case unit(s) are placed at the interface station 160TS of theconveyor 160CB according to the predetermined order out sequence forforming the mixed pallet MPL.

Here the load handling device LHD, LHD1, LHD2 grips both case units 7, 5within the payload section 4110PL in the manner described below (FIG. 10, Block 13020). The load handling device LHD, LHD1, LHD2 travels alongthe mast 4002 and interfaces with one or more output lifts 150B1 (FIG.10 , Block 13030). The load handling device LHD, 1HD1, LHD2 separatesthe case units 7, 5 within the payload section 4110PL, as will bedescribed in greater detail below, so that case unit(s) are separated inany suitable manner such as, for example, so that case unit(s) 5 isjustified towards the front of the payload section 4110PL and caseunit(s) 7 is justified towards the back of the payload section 4110PL(FIG. 10 , Block 13040). At least the case unit 5 is transferred to theinterface station 160TS (FIG. 10 , Block 13050). The load handlingdevice LHAD, LHD1, LHD2 retracts the transfer arm LHDA, LHDB to returnthe case unit(s) 7 to the payload section 4110PL (FIG. 10 , Block 13060)and grips the case unit 7 (FIG. 10 , Block 13020). The case unit(s) 7 istransported to another interface station 160TSA of output lift 150B1 (orplaced at the same interface station 160TS sequentially after placementof case unit(s) 5 at interface station 160TS) (FIG. 10 , Block 13030),justified toward the front of the payload section 4110PL (FIG. 10 ,Block 13040), and transferred to interface station 160TS, 160TSA, asdescribed above (FIG. 10 , Block 13050). In other aspects, depending onthe predetermined case unit output sequence, the load handling deviceLHD, LHD1, LHD2 places both case unit(s) 7, 5 at a commonlocation/position, such as simultaneously at a single interface stationof lifts 150B1.

As noted above, because the pusher bar 4110PR is a separate, standaloneaxis of the load handling device LHD, LHD1, LHD2 that operates free ofinterference from the pick head 4270 extension and lift axes, the pusherbar 4110PR can be operated substantially simultaneously with the liftingand/or extension of the transfer arm LHDA, LHDB. The combined axis moves(e.g. the simultaneous movement of the pusher bar 4110PR with thetransfer arm LHDA, LHDB extension and/or lift axes) provides forincreased payload handling throughput and effects the ordered (e.g.according to the predetermined load out sequence) multi-pick of two ormore case units from one or more interface station shelves 7000A-7000F,in one common pass of the vertical stack of interface stations TS. Forexample, referring again to FIGS. 7-7E during a transfer arm LHDA, LHDBmulti-pick/place sequence the pusher bar 4110PR is prepositioned (as thecase unit(s) and/or pickface are being picked and transferred into thepayload section 4110PL) to a location that is a predetermined distanceX2 away from the contact depth X3 (e.g. the depth of the tines occupiedby the case unit(s) and/or pickface 7 when being picked/placed frominterface station shelf 7000D or other case unit holding location) (FIG.11 , Block 1100). The distance X2 is a minimized distance that onlyallows sufficient clearance between pusher bar 110PR and the caseunit(s) to allow the case unit(s) to be seated on the rollers 4110RL. Asthe case unit(s) 7 are lowered onto the rollers 4110RL (FIG. 11 , Block1110) the distance travelled by the pusher bar 4110PR to contact thecase unit(s) 7 is a shorter distance X2 when compared to moving from aback side 4402 (relative to the Y direction and an access side 4401 ofthe payload section 4110PL) of the payload section 4110PL a distance X4as with conventional transport vehicles. When the case unit(s) 7 arelowered by the transfer arm LHDA, LHDB and transferred to the rollers4110RL so as to be solely supported by the rollers 4110RL, the pusherbar 4110PR is actuated to forward (relative to the lateral direction andan access side 4401 of the payload section 110PL) justify the caseunit(s) 7 (FIG. 11 , Block 1120). For example, the pusher bar 4110PB maypush the case unit(s) 7 in the Y direction so that the case unit(s)contact the fence 4110PF (which is located at the access side 4401 ofthe payload section 4110PL) so that a case unit reference datum may beformed through contact between the case unit(s) 7 and the fence 4110PF.In one aspect the pusher bar 4110PR may engage or otherwise grip thecase unit(s) 7 during transport of the case units (e.g. so as to holdthe case unit(s) against the fence 4110PF) for maintaining the caseunit(s) 7 in a predetermined spatial relationship with each other andthe reference frame REFL (FIG. 5E) of the load handling device LHD,LHD1, LHD2 (FIG. 11 , Block 1130). When placing the case unit(s) thepusher bar 4110PR, after justifying the case unit(s) 7 against the fence4110PF, is withdrawn (e.g. in the Y direction) from contact with thecase unit(s) 7 (FIG. 11 , Block 1140). Substantially immediately afterthe pusher bar 4110PR disengages the case unit(s) 7 one or more of thelift axis (e.g. in the Z direction) and extension axis (e.g. in the Ydirection) of the transfer arm LHDA, LHDB are actuated substantiallysimultaneously with the withdrawing movement of the pusher bar 4110PR(FIG. 11 , Block 1150). In one aspect both the lift and extension axesare actuated when the pusher bar is withdrawn from contact with the caseunit(s) 7 while in other aspect one of the lift and extension axes isactuated. As may be realized, the simultaneous movement of the transferarm 4110PA lift axis and/or extension axis with the withdrawal of thepusher bar 4110PR as well as the decreased distance the pusher moves tojustify the case unit(s) 7 decreases the time needed to transfer caseunit(s) 7 (e.g. that are sorted on the load handling device LHD, LHD1,LHD2) to and from the load handling device and increases throughput ofthe storage and retrieval system 100.

In another aspect of the disclosed embodiment, as may be realized, inthe multi-pick/place sequence multiple case units are substantiallysimultaneously carried and manipulated within the payload section 4110PLto further increase throughput of the storage and retrieval system 100and to effect the multi-pick/place sequence in accordance with apredetermined order out sequence. Referring also to FIG. 1 , the lift150B receives pick and place commands from, for example, control server120 (and/or warehouse management system 2500) and executes thosecommands (e.g. under the control of control server 120 (or a liftcontroller) for forming the ordered multi-pick. Here the lift moves theload handling device LHD, LHD1, LHD2 in the Z-direction to pick two ormore case units according to the predetermined order out sequence (FIG.12 , Block 1201A). In one aspect the manipulation of the case units 7, 5is a sorting of the case units (in other words picking and placing ofcase units according to the predetermined load out sequence) where thecases are positioned on the transfer arm LHDA, LHDB forpicking/placement of the case units and/or positioned so that the caseunits are not transferred and remain on the transfer arm LHDA, LHDBwhile other case units are transferred to and from the transfer armLHDA, LHDB. Here, the load handling device LHD, LHD1, LHD2 travels inthe Z direction and stops at a predetermined shelf 7000A-7000F of aninterface station TS, according to the predetermined order out sequence,where the load handling device LHD, LHD1, LHD2 picks one or more caseunits from the predetermined shelf 7000A-700F of the interface stationTS with a common transfer arm LHDA, LHDB where placement of the caseunits on the common transfer arm LHDA, LHDB corresponds to thepredetermined order out sequence as will be described in greater detailbelow (e.g. the case units are sorted on-the-fly, e.g. during transport,with the lift 150).

As an example of case manipulation on the bot 110, still referring toFIGS. 5E, 7, 7A-7E, case unit(s) 7 may be picked from a case unitholding location (e.g. such as interface station shelf 7000D foreffecting the ordered multi-pick (FIG. 12 , Block 1201B). As the caseunit(s) 7 is being transferred into the payload section 4110PL thepusher bar 4110PR may be pre-positioned (FIG. 12 , Block 1204) adjacentthe fence 4110PF so that the pusher bar 4110PR is positioned between thecase unit(s) 7 and the fence 4110PF when the case unit(s) 7 is loweredfor transfer to the rollers 4110RL (FIG. 12 , Block 1205). The pusherbar 4110PR is actuated to push the case unit(s) 7 (resting on therollers 4110RL) in the Y direction towards the back (e.g. rear) 4402 ofthe payload section 4110PL so that the case unit(s) 7 contacts ajustification surface 4273JS (FIG. 7 ) of the tines 4273A-4273E and isjustified to the back 4402 of the payload section 4110PL (FIG. 12 ,Block 1210).

In one aspect, the load handling device LHD, LHDA, LHD2 continues totraverse mast 4002 in the same direction (e.g. so that all of the caseunits in the ordered multi-pick are picked in the common pass of thevertical stack of interface stations TS with the load handling deviceLHD, LHD1, LHD2 travelling in a single direction) and stops at anotherdifferent predetermined shelf 7000A-7000F of a different interfacestation TS according to the predetermined order out sequence. As notedabove, the pusher bar 4110PR remains in contact with (e.g. grips) thecase unit(s) 7 during transport of the case unit(s) between interfacestation shelves 7000A-7000F so that the case unit(s) 7 remains in apredetermined location at the back 4402 of the payload section 4110PL(and/or at a predetermined location in the X direction) relative to thereference frame REFL of the lift 150B1 (FIG. 12 , Block 1215). To picksubsequent case units, from for example, the another interface stationshelf 7000B the pusher bar 4110PR is moved in the Y direction todisengage the case unit(s) 7 and the lift and extension axes of thetransfer arm LHDA, LHDB are actuated to retrieve another case unit(s) 5from the other interface station shelf 7000B (FIG. 12 , Block 1220).While the case unit(s) 5 are being picked the pusher bar 4110PR ispositioned in the Y direction adjacent the back 4402 of the payloadsection 4110PL so as to be located between the case units 7 and thejustification surface 4273JS of the tines 4273A-4273E (FIG. 12 , Block1225). The case unit(s) 5 are transferred into the payload section andlowered/placed on the rollers 4110RL (FIG. 12, Block 1230) so that thecase units 7, 5 are arranged relative to each other along the Y axis.The pusher bar 4110PR is actuated in the Y direction to push the caseunits 7, 5 towards the fence 4110PF to forward justify the case units 7,5 (FIG. 12 , Block 1234) and grip/hold the case units 7, 5 for transport(FIG. 12 , Block 1235). As may be realized, in one aspect the case units7, 5 are placed at the interface station 160TS together as a unit whilein other aspects the case units 7, 5 are sorted, e.g. transported to andplaced at different interface stations 160TS, 160TSA (FIG. 12 , Block1240).

Where the case units 7, 5 are sorted (FIG. 12 , Block 1250) forplacement at a common interface station 160TS, 160TSA (such as forsequential but chronologically spaced apart, placement of case unit) orat different interface stations 160TS, 160TSA, the case units 7, 5 areseparated from each other in the payload section 4110PL. For example,the pick head 4270 of the transfer arm LHDA, LHDB may be moved in the Zdirection to lift the case units 7, 5 from the rollers 4110RL by anamount sufficient to allow the pusher bar 4110PR to pass beneath thecase unit(s) (FIG. 13 , Block 1250A). As the case units 7, 5 are liftedthe pusher bar 4110PR is positioned along the Y direction so as to belocated between the case units 7, 5 (see FIG. 7E) (FIG. 13 , Block1250B). The pick head 4270 is lowered so that the case units 7, 5 aretransferred to the rollers 4110RL and so that the pusher bar is insertedbetween the case units 7, 5 (FIG. 13 , Block 1250C). The pusher bar4110PR is moved in the Y direction (e.g. to separate the case unit(s))to move case unit(s) 7 towards the back 402 of the payload section4110PL (e.g. against the justification surface 4273JS of the tines4273A-4273E or any other suitable position) while the case unit(s) 5remain at the front of the payload section 4110PL adjacent the fence4110PF (e.g. as shown in FIG. 7C) (FIG. 13 , Block 1250D). As may berealized, where the case units are held against the justificationsurface 4273JS of the tines during transport, the pusher bar is moved inthe Y direction (e.g. to separate the case unit(s)) to move case unit(s)5 towards the front 4401 of the payload section 4110PL (e.g. against thefence 4110PF or any other suitable position) while the case unit(s) 7remain at the back of the payload section 4110PL adjacent thejustification surface 4273JS. The pusher bar 4110PR may also be moved inthe Y direction to re-justify the case unit(s) 5 against the fence4110PF to position the case unit(s) on the tines 4273A-4273E forplacement at the interface station 160TS, 160TSA (FIG. 13 , Block1250E). As may be realized, with the case unit(s) 7 being positionedsubstantially against the justification surface 4273JS of the tines4273A-4273E (e.g. of the pick head 4270) the case unit(s) 5 can beplaced at the interface station 160TS, 160TSA substantially withoutinterference from the case unit(s) 7 (FIG. 13 , Block 1250F), e.g. thecase unit 7 is free from contacting case units disposed at the case unitholding location. The case unit(s) 7 is lowered/transferred back intothe payload section 4110PL (e.g. by retracting and lowering the transferarm 4110PA) (FIG. 13 , Block 1250G). The pusher bar 4110PR, which ispre-positioned between the justification surface 4273JS and the caseunit(s) 7, pushes the case unit(s) 7, which is disposed on the rollers4110RL, against the fence 4110PF to forward justify the case unit(s) 7for placement at the same or another interface station 160TS, 160TSA(e.g. different than the holding location that case unit (s) 5 wereplaced) (FIG. 13 , Block 1250H). The pusher bar 4110PR remains againstthe case unit(s) 7 for gripping (e.g. with the fence) the case unit(s)during transport to the other interface station 160TS, 160TSA (FIG. 13 ,Block 12501). The pusher bar 4110PR moves away from the case unit(s) 7and the transfer arm is actuated to lift and extend the pick head 4270for placing the case unit(s) 7 at the other interface station 160TS,160TSA (FIG. 13 , Block 1250J).

In one aspect, referring again to FIG. 5D, a lift with multipleindividually operable load handling devices LHD1, LHD2 picks and placescase units from more than one interface station TS at different storagelevels 130LA, 130LB and transfers the case units to the same ordifferent outbound conveyor interface stations TS (e.g. such as when thetransfer stations TS of one or more the outbound conveyors serving acommon lift 150 are stacked one above the other). Here, each of theindividually operable load handling devices LHD1, LHD2 picks and placescase units from the interface station shelves 7000A-7000F and deliversthe picked case units to the outbound conveyor 160CB in a mannersubstantially similar to the manner described above with respect toFIGS. 8, 9 and 10 . It is noted that in one aspect each load handlingdevice LHD1, LHD2 includes a single transfer arm LHDA, LHDB (see FIGS.5A, 5D) or more than one transfer arm LHDA, LHDB (see FIG. 5C) (e.g. oneload handling device include a single transfer arm while the other loadhandling device includes more than one transfer arm; both load handlingdevices include a single transfer arm; both load handling devicesinclude more than one transfer arm). The load handling devices LHD1,LHD2 in one aspect include the sorting and justification mechanismsdescribed above with respect to FIG. 5E.

The output lifts 150B1, 150B2 transfer the ordered multi-pick(s) placedon the shelves 7000A-7000L by the bots 110 to the output station 160UTalso in accordance with the predetermined order out sequence. Forexample, referring again to FIG. 6 , the pickfaces 1-22 are picked bythe lifts 150B1, 150B2 in sequenced order so that the pickfaces 1-22 aredelivered to the output station 160UT in the predetermined order(indicated by, for example, the number associated with each caseunit/pickface illustrated in FIG. 6 ) needed to form the mixed palletload MPL (FIG. 2 ) and/or in the predetermined order sequence (e.g. anorder out sequence) of picked items according to, for example, an order,fulfilling one or more customer orders, in which case units CU aresequenced for placement in one or more bag(s), tote(s) or othercontainer(s) TOT at an operator station 160EP. As such, each of theinterface stations TS of each lift 150B1, 150B2 forms a buffer thatholds one or more case unit(s) until the case unit(s) are needed andpicked by the respective lift 150B1, 150B2 for forming the mixed palletload.

Referring to FIG. 15 , in accordance with aspects of the disclosedembodiment, storage spaces arrayed on racks along picking aisles areprovided (FIG. 15 , Block 1600). Multiple level decks are also provided(FIG. 15 , Block 1610), where at least one deck level of the multiplelevel decks communicates with each aisle, where the multiple level decksand aisles define a rolling surface for an autonomous transport vehicleat each level of the multiple level decks. Racks at multiple rack levelsare accessed from a respective rolling surface that is common to themultiple rack levels (FIG. 15 , Block 1620), where the racks aredisposed along at least one aisle at each level of the multiple leveldecks. In one aspect, a vertical pitch between rack levels varies for aportion of a respective aisle. In one aspect, the vertical pitch betweenat least two rack levels of the portion of the respective aisle isrelated to another vertical pitch between at least two other rack levelsof another aisle portion of the respective aisle so that the autonomoustransport vehicle effects multiple picks in an ordered sequence in acommon aisle pass. In one aspect, the vertical pitch between at leasttwo rack levels of the portion of the respective aisle is related toanother vertical pitch between at least two other rack levels of anotheraisle portion of the respective aisle so that the vertical pitch and theother vertical pitch effects substantially filling a vertical spacebetween the multiple deck levels with stored items.

In accordance with one or more aspects of the disclosed embodiment, aproduct order fulfillment system includes multiple decks arrayed atdifferent levels and defining multilevel decks; at least one autonomoustransport vehicle disposed on each of the multilevel decks, andconfigured for holding and transporting a pickface on each deck; atleast one lift, traversing and connecting more than one level of themultilevel decks, and arranged for lifting and lowering the pickfacefrom the multilevel decks; and at least one pickface transfer station oneach deck interfacing between the autonomous transport vehicle on thedeck and the at least one lift to effect transfer of the pickfacebetween the autonomous transport vehicle and the at least one lift;wherein the at least one lift defines a fulfillment stream of mixed casepickfaces outbound from the multilevel decks to a load fill, and atleast one stream of the fulfillment stream has an ordered sequence ofstreaming pickfaces wherein the ordered sequence of streaming pickfacesis based on another fulfilment stream.

In accordance with one or more aspects of the disclosed embodiment, theload fill comprises mixed case pickfaces arranged in a predeterminedpickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, theordered sequence of streaming pickfaces from the at least one stream isrelated to the predetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, theordered sequence of streaming pickfaces from the at least one stream iscombined with a pickface from the other fulfillment stream to fill theload fill in the predetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, atleast one pickface from the other fulfillment stream in combination withthe ordered sequence of streaming pickfaces from the at least one streamforms a portion of consecutive ordered pickfaces of the predeterminedpickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, theat least one lift includes a first lift and the other fulfillment streamis defined by another of the at least one lift independent from thefirst lift.

In accordance with one or more aspects of the disclosed embodiment, thefirst lift has a lift platform arranged to support more than onepickface on the lift platform and is configured so that the first lifteffects picking or placing of the more than one pickface, correspondingto the ordered sequence of streaming pickfaces, with the lift platformat a common lift elevation.

In accordance with one or more aspects of the disclosed embodiment, thefirst lift effects picking or placing of the more than one pickfacesubstantially simultaneously.

In accordance with one or more aspects of the disclosed embodiment, theproduct order fulfillment system further includes a storage array withstorage racks having pickface storage locations arranged in multiplelevels corresponding to the different levels of the multilevel decks.

In accordance with one or more aspects of the disclosed embodiment, aproduct order fulfillment system includes multiple decks arrayed atdifferent levels and defining multilevel decks; at least one autonomoustransport vehicle disposed on each of the multilevel decks, andconfigured for holding and transporting a pickface on each deck; a firstlift, traversing and connecting more than one level of the multileveldecks, and arranged for lifting and lowering the pickface from themultilevel decks; a second lift, traversing and connecting more than onelevel of the multilevel decks, and arranged for lifting and lowering thepickface from the multilevel decks; and at least one pickface transferstation on each deck interfacing between the autonomous transportvehicle on the deck and the first and second lifts to effect transfer ofthe pickface between the autonomous transport vehicle and the first andsecond lifts; wherein the first lift defines a first fulfillment streamof mixed case pickfaces outbound from the multilevel decks to a loadfill, the second lift defines a second fulfillment stream of mixed casepickfaces outbound from the multilevel decks to the load fill, and thefirst fulfillment stream has as first ordered sequence of streamingpickfaces and the second stream has a second ordered sequence ofstreaming pickfaces, the first ordered sequence of streaming pickfacescomplementing the second ordered sequence of streaming pickfaces andbeing related to a load fill ordered sequence.

In accordance with one or more aspects of the disclosed embodiment, theload fill comprises mixed case pickfaces arranged in a predeterminedpickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, atleast one of the first ordered sequence of streaming pickfaces from thefirst fulfillment stream and the second ordered sequence of streamingpickfaces from the second fulfillment stream is related to thepredetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, thefirst ordered sequence of streaming pickfaces from the first fulfillmentstream is combined with a pickface from the second ordered sequence ofstreaming pickfaces from the second fulfillment stream to fill the loadfill in the predetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, atleast one pickface from the second fulfillment stream in combinationwith the first ordered sequence of streaming pickfaces from the firstfulfillment stream forms a portion of consecutive ordered pickfaces ofthe predetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, theat least one lift includes a first lift and the second fulfillmentstream is defined by another of the at least one lift independent fromthe first lift.

In accordance with one or more aspects of the disclosed embodiment, thefirst lift has a lift platform arranged to support more than onepickface on the lift platform and is configured so that the first lifteffects picking or placing of the more than one pickface, correspondingto the first ordered sequence of streaming pickfaces, with the liftplatform at a common lift elevation.

In accordance with one or more aspects of the disclosed embodiment, thefirst lift effects picking or placing of the more than one pickfacesubstantially simultaneously.

In accordance with one or more aspects of the disclosed embodiment, theproduct order fulfillment system further includes a storage array withstorage racks having pickface storage locations arranged in multiplelevels corresponding to the different levels of the multilevel decks.

In accordance with one or more aspects of the disclosed embodiment, amethod for product order fulfillment includes providing multiple decksarrayed at different levels and defining multilevel decks; disposing atleast one autonomous transport vehicle on each of the multilevel decksand holding and transporting, with the at least one autonomous transportvehicle, a pickface on each deck; lifting and lowering the pickface fromthe multilevel decks with at least one lift that traverses and connectsmore than one level of the multilevel decks; effecting transfer of thepickface between the autonomous transport vehicle and the at least onelift with at least one pickface transfer station on each deck thatinterfaces between the autonomous transport vehicle on the deck and theat least one lift; and defining, with the at least one lift, afulfillment stream of mixed case pickfaces outbound from the multileveldecks to a load fill, where at least one stream of the fulfillmentstream has an ordered sequence of streaming pickfaces and where theordered sequence of streaming pickfaces is based on another fulfilmentstream.

In accordance with one or more aspects of the disclosed embodiment, theload fill comprises mixed case pickfaces, the method further includesarranging the mixed case pickfaces in a predetermined pickface loadorder sequence.

In accordance with one or more aspects of the disclosed embodiment, theordered sequence of streaming pickfaces from the at least one stream isrelated to the predetermined pickface load order sequence.

In accordance with one or more aspects of the disclosed embodiment, themethod further includes combining the ordered sequence of streamingpickfaces from the at least one stream with a pickface from the otherfulfillment stream to fill the load fill in the predetermined pickfaceload order sequence.

In accordance with one or more aspects of the disclosed embodiment, themethod further includes forming a portion of consecutive orderedpickfaces of the predetermined pickface load order sequence with atleast one pickface from the other fulfillment stream in combination withthe ordered sequence of streaming pickfaces from the at least onestream.

In accordance with one or more aspects of the disclosed embodiment, theat least one lift includes a first lift, the method further comprisingdefining the other fulfillment stream by another of the at least onelift independent from the first lift.

In accordance with one or more aspects of the disclosed embodiment, thefirst lift has a lift platform arranged to support more than onepickface on the lift platform, the method further comprising effecting,with the first lift, picking or placing of the more than one pickface,corresponding to the ordered sequence of streaming pickfaces, with thelift platform at a common lift elevation.

In accordance with one or more aspects of the disclosed embodiment, themethod further includes effecting, with the first lift, picking orplacing of the more than one pickface substantially simultaneously.

In accordance with one or more aspects of the disclosed embodiment, themethod further includes providing a storage array with storage rackshaving pickface storage locations arranged in multiple levelscorresponding to the different levels of the multilevel decks.

In accordance with one or more aspects of the disclosed embodiment, aproduct order fulfillment system includes multiple decks arrayed atdifferent levels and defining multilevel decks; at least one autonomoustransport vehicle disposed on each of the multilevel decks, andconfigured for holding and transporting a pickface on each deck; atleast one lift, traversing and connecting more than one level of themultilevel decks, and arranged for lifting and lowering the pickfacefrom the multilevel decks; and at least one pickface buffer station oneach deck interfacing between the at least one autonomous transportvehicle on the deck and the at least one lift to effect transfer of thepickface between the autonomous transport vehicle and the at least onelift; wherein the at least one lift defines a fulfillment stream ofmixed case pickfaces streaming outbound from the multilevel decks to aload fill, and wherein the at least one pickface buffer station, of atleast one of the multilevel decks, commonly supports more than one ofthe mixed case pickfaces defining a portion of the streaming pickfacesin an ordered sequence of streaming pickfaces based on a predeterminedsequence of the load fill.

In accordance with one or more aspects of the disclosed embodiment, theat least one pickface buffer station forms a common pickface transferinterface for the at least one lift, so that the commonly supportedpickfaces are picked in common with the at least one lift.

In accordance with one or more aspects of the disclosed embodiment, theat least one pickface buffer station on more than one of the multileveldecks each commonly support more than one of the mixed case pickfacesdefining a portion of the streaming pickfaces in an ordered sequence ofstreaming pickfaces based on the predetermined sequence of the loadfill.

In accordance with one or more aspects of the disclosed embodiment, themixed case pickfaces defining the portion of the streaming pickfaces inthe ordered sequence commonly supported on the buffer station is basedon an ordered sequence of pickfaces on another buffer station of anotherfulfillment stream.

In accordance with one or more aspects of the disclosed embodiment, theproduct order fulfillment system further includes a controller incommunication with the at least one autonomous transport vehicle, thecontroller being configured to effect placement of pickfaces on the atleast one pickface buffer station based on the ordered sequence ofstreaming pickfaces.

It should be understood that the foregoing description is onlyillustrative of the aspects of the disclosed embodiment. Variousalternatives and modifications can be devised by those skilled in theart without departing from the aspects of the disclosed embodiment.Accordingly, the aspects of the disclosed embodiment are intended toembrace all such alternatives, modifications and variances that fallwithin the scope of the appended claims. Further, the mere fact thatdifferent features are recited in mutually different dependent orindependent claims does not indicate that a combination of thesefeatures cannot be advantageously used, such a combination remainingwithin the scope of the aspects of the invention.

What is claimed is:
 1. A product order fulfillment system comprising: atleast one elevated deck with an array of product storage locationsdistributed along the at least one elevated deck; at least oneautonomous transport vehicle disposed on each of the at least oneelevated deck, and configured for holding and transporting a pickface oneach deck; more than one lift, traversing and connecting the at leastone elevated deck and a base level, and arranged for lifting andlowering the pickface from the at least one elevated deck; and at leastone pickface buffer station on each deck interfacing each lift of themore than one lift to effect transfer of the pickface between the bufferstation on and off a selected lift of the more than one lift; whereinthe selected lift defines a fulfillment sequence of mixed case pickfacessequenced outbound at the base level from the selected lift and from theat least one elevated deck to a load fill, and wherein the at least onepickface buffer station, of the at least one elevated deck at theselected lift, supports one of the mixed case pickfaces so that thetransfer of the pickface between the buffer station on and off each liftdefines a portion of the sequenced pickfaces in an ordered sequence ofsequenced pickfaces based on a predetermined sequence of the load fill.2. The product order fulfillment system of claim 1, wherein the at leastone pickface buffer station forms a common pickface transfer interfaceat each deck for the fulfillment sequence defined by the more than onelift, so that the pickfaces are transferred on and off the more than onelift within the fulfillment sequence.
 3. The product order fulfillmentsystem of claim 1, wherein the at least one pickface buffer station oneach of the at least one elevated deck each supports one or more of themixed case pickfaces so that the transfer of the pickface between thebuffer station on and off the selected lift of the more than one liftdefines a portion of the sequenced pickfaces in an ordered sequence ofsequenced pickfaces based on the predetermined sequence of the loadfill.
 4. The product order fulfillment system of claim 1, whereintransfer of the mixed case pickfaces between the buffer station on andoff each lift defining the portion of the sequenced pickfaces in theordered sequence is based on an ordered sequence of pickfaces on anotherbuffer station of another fulfillment sequence.
 5. The product orderfulfillment system of claim 1, further comprising a controller incommunication with the at least one autonomous transport vehicle, thecontroller being configured to effect placement of pickfaces on the atleast one pickface buffer station based on the ordered sequence ofsequenced pickfaces.
 6. The product order fulfillment system of claim 1,further comprising a storage array with storage racks having pickfacestorage locations arranged in multiple levels corresponding to thedifferent levels of the at least one elevated deck.
 7. The product orderfulfillment system of claim 1, wherein transfer of the mixed casepickfaces between the buffer station on and off the selected liftchanges a buffered order of pickfaces supported at the buffer station atthe selected lift of the at least one elevated deck to the orderedsequence of the portion of sequenced pickfaces.
 8. The product orderfulfillment system of claim 7, further comprising a controllerconfigured to effect placement of pickfaces on the at least one pickfacebuffer station based on the buffered order.
 9. A method for productorder fulfillment, the method comprising: providing at least one deckwith an array of product storage locations distributed along the atleast one elevated deck; disposing at least one autonomous transportvehicle on each of the at least one elevated deck and holding andtransporting, with the at least one autonomous transport vehicle, apickface on each deck; lifting and lowering the pickface from the atleast one elevated deck with more than one lift that traverses andconnects the at least one elevated deck and a base level; effectingtransfer of the pickface between at least one pickface buffer station onand off a selected lift of the more than one lift; and defining, withthe selected lift, a fulfillment sequence of mixed case pickfacesoutbound at the base level from the selected lift and from the at leastone elevated deck to a load fill, where the at least one pickface bufferstation, of the at least one elevated deck at the selected lift,supports at least the mixed case pickfaces so that the transfer of thepickface between the buffer station on and off the lift defines aportion of the sequenced pickfaces in an ordered sequence of sequencedpickfaces based on a predetermined sequence of the load fill.
 10. Themethod of claim 9, wherein the at least one pickface buffer stationforms a common pickface transfer interface at each deck for thefulfillment sequence defined by the more than one lift, so that thepickfaces are transferred on and off the more than one lift within thefulfillment sequence.
 11. The method of claim 9, wherein the at leastone pickface buffer station on each of the at least one elevated deckeach supports one or more of the mixed case pickfaces so that thetransfer of the pickface between the buffer station on and off each liftdefines a portion of the sequenced pickfaces in an ordered sequence ofsequenced pickfaces based on the predetermined sequence of the loadfill.
 12. The method of claim 11, wherein the transfer of the mixed casepickfaces between the buffer station on and off each lift defining theportion of the sequenced pickfaces in the ordered sequence is based onan ordered sequence of pickfaces on another buffer station of anotherfulfillment sequence.
 13. The method of claim 9, further comprisingeffecting, with a controller in communication with the at least oneautonomous transport vehicle, placement of pickfaces on the at least onepickface buffer station based on the ordered sequence of sequencedpickfaces.
 14. The method of claim 9, further comprising providing astorage array with storage racks having pickface storage locationsarranged in multiple levels corresponding to the different levels of theat least one elevated deck.
 15. The method of claim 9, wherein transferof the mixed case pickfaces between the buffer station on and off theselected lift changes a buffered order of pickfaces supported at thebuffer station at the selected lift of the at least one elevated deck tothe ordered sequence of the portion of sequenced pickfaces.
 16. Themethod of claim 15, further comprising effecting, with a controller,placement of pickfaces on the at least one pickface buffer station basedon the buffered order.